Polyester film for decorative plate or decorative sheet

ABSTRACT

The present invention relates to a polyester film for decorative plate or decorative sheet, which comprises a base polyester film and a coating layer formed on at least one surface of said base film, and which has an optical density of 0.1 to 5.0 and longitudinal and transverse heat shrinkage percentages of not less than -10.0% and not more than +10.0% after said film is heat-treated at 180° C. for 5 minutes.

BACKGROUND OF THE INVENTION

The present invention relates to a polyester film for a decorative plateor decorative sheet. More particularly, the present invention relates toa polyester film for a decorative plate laminated by clear film, whichcomprises a coated polyester film having specific properties, and showsan excellent suitability for decorative plate.

The decorative plate has a laminated structure in which at least a filmlayer and a picture-printed layer are in turn superimposed over asurface of substrate, and generally means a building material (surfacematerial) capable of being dealt as an independent product. Thedecorative sheet means a decorative material (surface material) which isadhered to a surface of substrate for various products such asfurniture, building components or housing appliances and provided on asurface thereof with a picture-printed layer. Accordingly, the filmlayer and the picture-printed layer laminated over the surface ofsubstrate of the decorative plate, are components of the decorativesheet.

As a sheet material interposed between the substrate and thepicture-printed layer of the decorative plate or a sheet material (film)used in the decorative sheet, vinyl chloride resin sheets are mostgenerally used. However, in the case where the vinyl chloride resinsheet is used, there arise such problems that a plasticizer blended inthe sheet material is transferred to an adhesive layer formed on itssurface to be adhered, resulting in deteriorated adhesion thereof, orthat the vinyl chloride resin sheet suffers from elongation or shrinkageby heating due to low thermal dimensional stability thereof, therebycausing wrinkles thereon. Further, in recent years, there has been anincreasing demand for producing decorative plates or decorative sheetswithout using the vinyl chloride resin sheet, from a standpoint ofenvironmental protection.

Meanwhile, as described above, since decorative plates and decorativesheets are used as a surface material, picture patterns having a highdesign value are generally formed on a surface thereof. Therefore, it isextremely important to adjust or control color tones of the decorativeplates or decorative sheets in order to obtain appropriate contrastsbetween the picture patterns or delicate contrasts of shade and shadowthereon. Specifically, as the substrates of the decorative plates or thesubstrates to which decorative sheets are attached, various materialssuch as plywood, e.g., particle boards, steel boards or the like havebeen used. In general, these substrates have a variety of color toneswhich are different from each other, even if they are formed from thesame material.

Accordingly, if individual films for the decorative sheet have adeteriorated hiding power, the color tone of the substrate adverselyaffects that of the surface of the decorative plate or decorative sheet,so that inherent high design value of the picture patterns formedthereon are damaged. For this reason, it is required that the sheetmaterials or films for the decorative plates or decorative sheets have ahigh hiding power, thereby enabling these sheet materials or films to bewidely applicable to substrates having various color tones.

On the other hand, biaxially-oriented polyester films, typicallypolyethylene telephthalate films have been widely utilized in variousfields because of their excellent properties. As disclosed in JapanesePatent Application Laid-Open (KOKAI) No. 7-17005, thesebiaxially-oriented polyester films have been proposed so as to be usedonly as surface materials for decorative plates. However, there has notyet been any proposal in which the biaxially-oriented polyester filmsare interposed between the substrate and the picture printed layer, inother words, that the biaxially-oriented polyester films are used as asheet material or film for decorative sheets.

Meanwhile, polyester films are generally deteriorated in adhesion tovarious materials as compared with vinyl chloride resin films or sheets.Accordingly, in the case where the polyester films are used instead ofthe vinyl chloride resin films or sheets, there are causeddisadvantages, e.g., deteriorated adhesion to wood as the substrate. Thedecorative plates are used to decorate surfaces of various furniture,doors or the like. Therefore, the occurrence of delamination orseparation of the film from the substrate should be prevented becausethe delamination or separation shows that the decorative plates areimitation products.

As a material for a sash bar for receiving an aluminum sash, in manycases, there have been used decorative plates composed of a woodenmaterial. In this case, the decorative plates used as the sash bar areexposed to severe change in temperature between summer and winterseasons together with load of the aluminum sash. Under such acircumstance, if the adhesion between the film and the substrate isdeteriorated, the delamination or separation of the film from thesubstrate is likely to occur, thereby causing undesirable mountainrange-like undulations along the sash bar. In addition, when it isintended to form picture patterns having a high design value on the filmby printing or the like, there arise problems such as deterioratedsuitability for printing, deteriorated wettability for ink or adhesive,occurrence of delamination or separation of the laminated printed layerdue to low adhesion thereof.

Further, with respect to the decorative plates laminated by clear film,there arises the below-mentioned problems.

Decorative plates having such a laminated structure in which an adhesivelayer, a film layer and a picture printed layer are in turn superimposedon a substrate are called "printed decorative plate". The decorativeplates having such a laminated structure in which a first adhesivelayer, an inner film layer, a picture printed layer, a second adhesivelayer and an outer film layer are in turn superimposed on a substrateare called "decorative plate laminated by clear film". Incidentally, asthe substrates, wood-based boards such as plywood or particle boards,inorganic boards, steel boards or the like can be appropriately used.

Especially, the decorative plate laminated by clear film has suchtechnical advantages that (i) an appropriate protection for thepicture-printed layer can be attained by the outer film layer, (ii) whenthe outer film layer comprises a transparent film, the decorative platecan exhibit a high-grade picture pattern, and (iii) when the outer filmlayer comprises an embossed film, the decorative plate with athree-dimensional moire finishing can be produced. For these reasons,the decorative plates laminated by clear film can be used inhigher-grade applications as compared with the printed decorativeplates.

Owing to the afore-mentioned advantages, the decorative plates laminatedby clear film can be applied to front face decorations of variousfurniture, doors or the like. Especially, in the case of furniture,doors or the like comprising a wood-based board, the corners thereof aredefined by adjacent two flat portions which are crossed at a rightangle. These corners can be formed by bending the afore-mentioneddecorative plate.

The bending of the decorative plate has been generally performed by aso-called V-cutting process. In the V-cutting process, V-shaped notchesare formed on a surface of a substrate of the decorative plate such thatthe depth of each notch is slightly smaller than the thickness of thesubstrate. The decorative plate is then bent at these V-shaped notchessuch that the notched surface of the decorative plate is located inside.For this reason, the suitability for bending deformation process, of thedecorative plate is highly relied upon those of the films used therein.Especially, in the case of the decorative plates laminated by clear filmin which inner and outer films are used, it is required that these filmsshow more excellent suitability for bending deformation process ascompared with in the case of the printed decorative plate having onlyone film. If the films are deteriorated in suitability for bendingdeformation process, the bent shape of the decorative plate cannot bekept stable when subjected to V-cutting and bending processes, butreadily returns back to its original flat shape. Further, at this time,there is a likelihood in which the decorative sheet comprising the innerfilm layer, the picture-printed layer, the adhesive layer and the outerfilm layer is separated from the substrate, so that the decorative plateis deteriorated in its appearance or design value. Therefore, it isrequired that the films used in the decorative plate laminated by clearfilm shows excellent suitability for V-cutting and bending processes.

Also, in the case where the decorative plate is used as surfacematerials for furniture, doors or the like, it is inevitably broughtinto contact with, for example, tip ends of a cleaner, nails or thelike. If the films adhered to the substrate of the decorative plate havelow self-healing properties (restoring properties), dents caused thereonby the afore-mentioned contact are left as they are, so that a highdesign value of the picture pattern of the picture-printed layer cannotbe maintained. In addition, if the films adhered to the substrate of thedecorative plate do not have an appropriate strength or rigidity,plastic deformation thereof becomes increased and it is impossible toremove such dents by self-healing. Especially, in the case of thedecorative plate laminated by clear film, it is required that the filmsto be adhered to the substrate of the decorative plate are excellent inself-recovery for dent deformation (resistance to impact deformation)which is a property combining the afore-mentioned self-healingproperties and strength or rigidity.

Hitherto, as films for the decorative plates, vinyl chloride resin filmshave been most generally used. The vinyl chloride resin films have alsobeen applied to many decorative plates laminated by clear film. Thevinyl chloride resin films are readily deformable, and therefore, show agood suitability for V-cut processing. However, since the vinyl chlorideresin films are deteriorated in resistance to impact deformation due tolack of appropriate mechanical strength, there arises a problem in whichthe thickness of the film must be sufficiently increased, or the like.

In addition, since the vinyl chloride resin films cause environmentalproblems upon burning, there is a strong demand for developing filmscomprising other materials instead of the vinyl chloride resin films.Further, when the vinyl chloride resin film is adhered to a substratethrough an adhesive layer, there arises such a problem that aplasticizer or a stabilizer contained in vinyl chloride resin istransferred to the adhesive layer, resulting in deteriorated adhesionthereof to the substrate. Furthermore, since the vinyl chloride resinfilms inherently show large elongation or shrinkage upon heating due tolow thermal dimensional stability thereof, there also arises a problemin which the decorative plate laminated by the vinyl chloride resin filmis likely to suffer from wrinkles on a surface thereof.

Incidentally, with respect to decorative plates using other films thanthe vinyl-chloride resin films, there have been proposed a decorativeplate in which a laminated material comprising a polyolefin-basedsynthetic paper as base film or a flexible polyester film as a base filmis used (Japanese Patent Application Laid-Open (KOKAI) No. 7-17005(1995)); a decorative plate in which a laminated material comprising athermoplastic transparent elastomer film selected from the groupconsisting of styrene-based films, olefin-based films, urethane-basedfilms, fluororubber-based films, polyamide-based films and ester-basedfilms, or an polyolefin-based resin is used (Japanese Patent ApplicationLaid-Open (KOKAI) No. 6-79830 (1995)); or the like.

However, the afore-mentioned conventional decorative plates using thepolyolefin-based resin films are not suitable for furniture or interiorbuilding materials, because these decorative plates show a largecalorific value upon burning, e.g., upon fire. For this reason, there isa demand for decorative plates using other films than thepolyolefin-based resin films.

Polyester films are advantageously used for the decorative platesbecause of relatively low calorific value and less environmental problemupon burning thereof. Further, the polyester films are excellent inthermal dimensional stability. However, the polyester films are usuallydeteriorated in the suitability for V-cut processing. In addition, inmany cases, the polyester films are unsatisfactory in adhesion toplywood. Also, when it is intended to form a picture printed layer onthe polyester film, the adhesion thereto is unsatisfactory, because thepolyester films are deteriorated in adhesion to an adhesive layer or thepicture printed layer. Accordingly, there are conventionally known nodecorative plates laminated by clear film, which are excellent insuitability for V-cut processing, in resistance to impact deformationand in adhesion property, and which cause less environmental pollutionupon burning.

As a result of the present inventors' earnest studies for solving theabove problems, it has been found that by using a polyester film coatedon at least one surface thereof with a coating layer and having aspecific optical density, a specific coefficient of thermal shrinkageand a specific tensile modulus, as a film layer of a decorative plate inwhich at least the film layer and a picture printed layer are in turnlaminated over a surface of a substrate, or as an inner film layer of adecorative plate laminated by clear film in which at least a firstadhesive layer, the inner film layer, a picture printed layer, a secondadhesive layer and an outer film layer are in turn laminated over asubstrate, there can be obtained the decorative plate or the decorativeplate laminated by clear film which is free from the afore-mentionedproblems and can show excellent properties. The present invention hasbeen attained on the basis of the above finding.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a polyester film fordecorative plate or decorative sheet which is free from environmentalproblems upon burning, enables picture patterns having a high designvalue to be formed thereon without being adversely influenced by colortone of substrate, and shows an excellent thermal dimensional stabilityand an excellent adhesion to the substrate.

It is another object of the present invention to provide a polyesterfilm for decorative plate laminated by clear film, which is considerablyimproved in suitability for V-cut processing and in resistance to impactdeformation, and is free from environmental pollution upon burning.

To accomplish the aim, in a first aspect of the present invention, thereis provided a polyester film for decorative plate or decorative sheet,which comprises a base polyester film and a coating layer formed on atleast one surface of the said base film, and which-and an opticaldensity of 0.1 to 5.0 and longitudinal and transverse heat shrinkagepercentages of not less than -10.0% and not more than +10.0% after thesaid film is heat-treated at 180° C. for 5 minutes.

In a second aspect of the present invention, there is provided adecorative plate comprising a substrate and at least a polyester filmlayer comprising the polyester film as defined in the first aspect and apicture-printed layer, the said film layer and said picture-printedlayer being in turn laminated on the said substrate.

In a third aspect of the present invention, there is provided adecorative sheet comprising a polyester film layer comprising thepolyester film as defined in the first aspect and a picture-printedlayer formed on at least one surface of the said film layer.

In a fourth aspect of the present invention, there is provided apolyester film for decorative plate laminated by clear film, whichcomprises a base polyester film and a coating layer formed on at leastone surface of the said base film and which has longitudinal andtransverse tensile moduli of not more than 600 kg/mm².

In a fifth aspect of the present invention, there is provided adecorative plate laminated by clear film, which comprises a substrate,at least a first adhesive layer, an inner film layer comprising thepolyester film as defined in the fourth aspect, a picture-printed layer,a second adhesive layer and an outer film layer, and which layers are inturn laminated over the said substrate.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is described in detail below. The wording of"polyesters" used herein means polymers having ester groups, which areproduced by the polycondensation of dicarboxylic acid with diol orhydroxy-carboxylic acid.

Examples of the dicarboxylic acids include terephthalic acid,isophthalic acid, adipic acid, azelaic acid, sebacic acid,2,6-naphthalene-dicarboxylic acid, 1,4-cyclohexane-dicarboxylic acid orthe like. Examples of the diols include ethylene glycol,1,4-butane-diol, diethylene glycol, triethylene glycol, neopentylglycol, 1,4-cyclohexane-dimethanol, polyethylene glycol or the like.Examples of the hydroxy-carboxylic acids include p-hydroxy-benzoic acid,6-hydroxy-2-naphthoic acid or the like.

Typical examples of the polyesters include polyethylene-terephthalate,polyethylene-2,6-naphthalate or the like. The polyesters used in thepresent invention may be in the form of homopolymers or copolymersprepared by copolymerizing a third component therewith.

As described above, the decorative sheets according to the presentinvention can be used for substrates having various color tones.Accordingly, it is important that the decorative sheet according to thepresent invention has a high hiding power such that the color tone ofthe substrate neither adversely affects that of the decorative sheet nordamage a high design value of the picture pattern formed therein. Forthis reason, in accordance with the present invention, the opticaldensity of the polyester film used in the decorative sheet is 0.1 to5.0. The afore-mentioned optical density of the polyester film ispreferably 0.2 to 4.0, more preferably 0.5 to 3.0, still more preferably1.3 to 3.0.

The hiding power which is represented in terms of the afore-mentionedoptical density, can be imparted by incorporating inorganic or organicparticles into the polyester film. Examples of the inorganic or organicparticles include titanium dioxide, calcium carbonate, barium sulfate,aluminum oxide, silicon dioxide, carbon black, iron oxide, chromiumoxide or the like. Any other particles than the above-exemplified onescan also be used in the present invention as far as they can satisfy therequirement for the above-defined optical density. Further, in order toenhance a dispersibility in polyester and a weather resistance of theresultant decorative plate, these particles may also be surface-treatedwith an oxide of aluminum, silicon, zinc or the like and/or an organiccompound.

Alternatively, in order to impart the hiding power to the polyesterfilm, isolated small cells or bubbles may also be incorporated therein.Specifically, the incorporation of the isolated small cells or bubblesin the polyester film may be performed by a method in which a smallamount of polyolefin non-compatible with the polyester is added to thepolyester and the blended material is then subjected to an elongationand a heat-set, or a method in which an inert gas is contained in thepolyester film.

When the optical density of the polyester film is less than 0.1, thecolor tone of the substrate to which the polyester film is adhered, mayadversely affect that of the picture pattern formed on the surface ofthe decorative sheet, thereby failing to accomplish the aim of thepresent invention. On the other hand, when the optical density of thepolyester film is more than 5.0, the polyester film may often suffersfrom breakage upon the production thereof or be deteriorated in itsmechanical strength.

By using the polyester film according to the present invention, thedecorative sheet possessing the picture pattern having a high designvalue on the surface thereof can be formed without adverse influence bythe color tone of the substrate. Accordingly, when the decorative sheetcomprising the polyester film according to the present invention and apicture pattern is adhered to the surface of the substrate, it becomespossible to produce an excellent printed decorative plate. Also, theafore-mentioned decorative sheet is suitably applied to buildingmaterials, furniture, household appliances or the like. Further, in theproduction of the printed decorative plate, the polyester film may firstbe subjected, at the surface thereof, to a hiding-printing treatment andthen to a picture-printing treatment. Alternatively, the polyester filmon which the picture pattern have been printed, may be embossed and thencovered with a top coat.

Since the polyester film according to the present invention exhibits anexcellent hiding power, only a single polyester film can be used toproduce a printed decorative sheet or plate. Also, the polyester film oftwo or more layers may be used for the production of decorative sheetsor plates. For example, a plurality of the polyester films according tothe present invention may be adhered to the surface of the substratesuch as plywood. By such a multi-layer structure of the polyester film,the surface of the decorative sheet or decorative plate can be readilyembossed.

If the decorative sheet has a deteriorated dimensional stability,wrinkles are generated thereon, resulting in damage to the high designvalue of the picture pattern. For this reason, in accordance with thepresent invention, it is required that the polyester film exhibitslongitudinal and transverse heat shrinkage percentages both being notless than -10.0% and not more than +10.0% after heat-treated at 180° C.for 5 minutes. The afore-mentioned heat shrinkage percentages arepreferably in the range of not less than -7.0 and not more than +7.0%.Especially, it is more preferred that the longitudinal heat shrinkagepercentages is not less than -4.0% and not more than +4.0% andtransverse heat shrinkage percentages is not less than -1.0% and notmore than +1.0%. When the heat shrinkage percentages are less than -10%,i.e., when the elongation thereof exceeds 10%, the surface of thedecorative sheet may be unsuitably swelled up, so that its appearancemay be considerably deteriorated. On the other hand, when the heatshrinkage percentages are more than +10%, there may arise such problemsthat the decorative sheet is separated from surfaces of the buildingmaterials, furniture or the like, or the picture pattern is distorted.

Incidentally, wood materials have been favorably used for furniture,building materials, household appliances or the like. Specifically,ligneous color tones are favorably adopted because a space surrounded bysuch ligneous color tones, as seen in Japanese houses, contributes tomental rest or serenity of residents. In order to attain such effects,it is preferred that the polyester film itself have a color toneharmonious with the ligneous picture pattern in addition to the hidingpower and the dimensional stability.

Further, the afore-mentioned polyester film according to the presentinvention can be also used as a film for the decorative plate laminatedby clear film. Accordingly, the obtained decorative plate laminated byclear film can exhibit an excellent self-recovery for dent deformation(resistance to impact deformation) due to a peculiar property of thepolyester film itself. Furthermore, it is preferable that the polyesterfilm used as the film for the decorative plate laminated by clear filmhas longitudinal and transverse tensile moduli of not more than 600kg/mm² from the standpoint of improving its suitability for V-cutprocessing. The longitudinal and transverse tensile moduli of thepolyester film are preferably in the range of 190 to 550 kg/mm², morepreferably 190 to 500 kg/mm².

If the longitudinal and transverse tensile moduli are more than 600kg/mm², the polyester film may be apt to return back to its originalflat shape due to the elastic deformation when subjected to V-cuttingand bending finish processes, so that the bent shape of the polyesterfilm may not be maintained stably for a long period of time. On theother hand, when the longitudinal and transverse tensile moduli of thepolyester film are less than 190 kg/mm², there may be a tendency inwhich wrinkles or the like are caused in the polyester film due to atension force thereof generated when it is adhered to the substrate,etc., so that the resulting decorative plate may suffer from a wavysurface.

The thickness of the polyester film according to the present inventionis generally in the range of 5 to 100 μm, preferably 12 to 80 μm. Whenthe thickness of the polyester film is less than 5 μm, the substrate maybe highly susceptible to an impact applied to a surface of thedecorative plate. As a result, especially if the substrate has a highsurface hardness, a clear layer or a picture-printed layer formed on thesurface of the decorative plate, which has a lower hardness than that ofthe substrate, may be more severely damaged. On the other hand, when thethickness of the polyester film is more than 100 μm, a force requiredfor bending the polyester film is increased, so that it may be difficultto maintain the bent shape of the decorative plate. the surface of thedecorative plate is caused to exhibit more bluish color tone theresultant decorative plate may have a desolate appearance, andtherefore, the warm color tone inherent to a ligneous material may bedamaged. In accordance with the present invention, the below-mentioneddyes and/or pigments can be incorporated into the polyester film.

Examples of the dyes include natural dyes such as indigo, or syntheticdyes such as azo dyes, anthraquinone dyes, indigoid dyes, sulfur dyes,triphenyl methane dyes, pyrazolone dyes, stilbene dyes, diphenyl methanedyes, xanthene dyes, alizarin dyes, acridine dyes, quinoneimine dyes(e.g., azine dyes, oxazine dyes or thiazine dyes), thiazole dyes,methine dyes, nitro dyes, nitroso dyes, cyanine dyes or the like,preferably anthraquinone dyes.

Examples of the pigments include organic pigments such asphthalocyanine-based pigments, dioxazine-based pigments,anthraquinone-based pigments or the like, or inorganic pigments such astitanium white, zinc white, white lead, carbon black, red oxide,vermilion, cadmium red, chrome yellow, ultramarine blue, cobalt blue,cobalt violet, zinc chromate or the like, preferably titanium white,carbon black or red oxide.

In accordance with the present invention, a method of adding theaforementioned particles, dyes and/or pigments to the polyester film isnot particularly restricted but any known method can be used therefor.

The polyester film for the decorative plate, the decorative sheet or thedecorative plate laminated by clear film according to the presentinvention comprises a polyester base film and a coating layer formed onat least one surface of the polyester base film. A coating material usedfor the preparation of a coating solution can be optionally selectedfrom known coating materials. From the standpoint of adhesion to thepolyester base film, it is preferred that the coating material containsat least one compound selected from the group consisting of a polyesterresin, an acrylic resin, a polyurethane resin, an amino resin, an epoxyresin, an oxazoline resin and a coupling agent.

Examples of polycarboxylic acids as a constituent of the afore-mentionedpolyester resin may include terephthalic acid, isophthalic acid,ortho-phthalic acid, phthalic acid, 4,4'-diphenyl dicarboxylic acid,2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid,1,4-cyclohexane dicarboxylic acid, 2-potassium-sulfo-terephthalic acid,5-sodium-sulfo-isophthalic acid, adipic acid, azelaic acid, sebacicacid, dodecane dicarboxylic acid, glutaric acid, succinic acid,trimellitic acid, trimesic acid, trimellitic anhydride, phthalicanhydride, p-hydroxy benzoic acid, monopotassium trimellitate,esterifiable derivatives thereof or the like. Among them, preferredpolycarboxylic acids are terephthalic acid, isophthalic acid,2,6-naphthalene dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid or5-sodium-sulfo-isophthalic acid.

Examples of polyhydroxy compounds as a constituent of theafore-mentioned polyester resin may include ethylene glycol,1,2-propylene glycol, 1,3-propylene glycol, 1,3-propane diol, 1,4-butanediol, 1,6-hexane diol, 2-methyl-1,5-pentane diol, neopentyl glycol,1,4-cyclohexane dimethanol, p-xylene glycol, bisphenol A-ethylene glycoladduct, diethylene glycol, triethylene glycol, polyethylene glycol,polypropylene glycol, polytetramethylene glycol, polytetramethyleneoxideglycol, dimethylol propionic acid, glycerol, trimethylol propane, sodiumdimethylolethyl sulfonate, potassium dimethylol propionate or the like.Among them, preferred polyhydroxy compounds are ethylene glycol,1,4-butane diol, neopentyl glycol, 1,4-cyclohexane dimethanol, bisphenolA-ethylene glycol adduct, or polyethylene glycol.

The polyester resin can be synthesized by ordinary polycondensation ofthe afore-mentioned polycarboxylic acid and polyhydroxy compound. Inaddition to the afore-mentioned resins, composite polymers containingpolyester components such as so-called acryl-grafted polyesters which isdescribed in Japanese Patent Application Laid-Open (KOKAI) No. 1-165633,can also be used as the polyester resin.

The acrylic resins used in the present invention, may be polymersprepared from polymerizable monomers having carbon double bonds, such astypically acrylic or methacrylic monomers. These polymers may be in theform of homopolymers or copolymers. Further, copolymers of theafore-mentioned polymers with the other polymers can also used as theacrylic resins. Examples of the other polymers may include polyesters,polyurethanes, epoxy resins or the like. The copolymers may be in theform of block copolymers, graft copolymers or the like.

Furthermore, in the present invention, there can also be used polymersobtained by polymerizing polymerizable monomers having carbon doublebonds in a polyester solution or a polyester dispersion (occasionally, amixture of these polymers), polymers obtained by polymerizingpolymerizable monomers having carbon double bonds in a polyurethanesolution or a polyurethane dispersion (occasionally, a mixture of thesepolymers), or polymers obtained by polymerizing polymerizable monomershaving carbon double bonds in a solution or dispersion containing theother polymers (occasionally, a mixture of these polymers).

Typical examples of the afore-mentioned polymerizable monomers havingcarbon double bonds may include various carboxyl-containing monomerssuch as acrylic acid, methacrylic acid, crotonic acid, itaconic acid,fumaric acid, maleic acid, citraconic acid, or salts thereof; varioushydroxyl-containing monomers such as 2-hydroxy-ethyl-acrylate,2-hydroxy-ethyl methacrylate, 2-hydroxy-propyl acrylate,2-hydroxy-propyl mathacrylate, 4-hydroxy-butyl acrylate, 4-hydroxy-butylmethacrylate, monobutyl-hydroxy fumarate or monobutyl-hydroxy itaconate;various acrylic or methacrylic esters such as methyl acrylate, methylmethacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate,propyl methacrylate, butyl acrylate, butyl methacrylate, lauryl acrylateor lauryl methacrylate; various nitrogen-containing vinyl-based monomerssuch as acrylamide, methacrylamide, diacetone acrylamide, N-methylolacrylamide, acrylonitrile or methacrylonitrile; various styrenederivatives such as styrene, α-methyl styrene, divinyl benzene or vinyltoluene; various vinyl esters such as vinyl acetate or vinyl propionate;various silicon-containing polymerizable monomers such asγ-methacryloxy-propyl-trimethoxy silane, vinyl-trimethoxy silane or"THYRAPRENE FM-07", produced by Chisso Corporation. (methacrylyl siliconmacromer); phosphorus-containing vinyl-based monomers; various vinylhalides such as vinyl chloride, vinylidene chloride, vinyl fluoride,vinylidene fluoride, trifluorochloroethylene, tetrafluoroethylene,chlorotrifluoroethylene, hexafluoropropylene; various conjugated dienessuch as butadiene; or the like. Among them, preferred polymerizablemonomers having carbon double bonds are acrylic acid, methacrylic acid,2-hydroxy-ethyl-acrylate, 2-hydroxy-ethyl methacrylate, methyl acrylate,methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate,butyl methacrylate, acrylamide, N-methylol acrylamide, acrylonitrile orstyrene.

As methods for polymerization of the afore-mentioned acrylic ormethacrylic monomers, there can be exemplified a method of mixing anorganic solvent, the monomer and a polymerization initiator together andheating the mixture while stirring so as to conduct the polymerizationof the monomer, a high-pressure polymerization method using anautoclave, emulsion-type or suspension-type polymerization method inwhich water is used instead of an organic solvent, if required togetherwith a surfactant, or the like.

Examples of the afore-mentioned polymerization initiators may includeinorganic peroxides such as ammonium persulfate or hydrogen peroxide;acyl peroxides such as benzoyl peroxide; various alkyl hydroperoxidessuch as tert-butyl hydroperoxide or p-menthane hydroperoxide; variousdialkyl peroxides such as di-tert-butyl peroxide; various azo-basedcompounds such as azo-bis-isobutylonitrile or azo-di-tert-butane; or thelike.

The afore-mentioned inorganic or organic peroxide can be used incombination with a reducing agent to form a so-called redox-seriescatalyst. In this case, the respective components can be composed of asingle compound or a plurality of compounds in combination.Incidentally, as the reducing agents, there can be used, for example,organic amines, L-ascorbic acid, L-sorbic acid, cobalt naphthenate,cobalt octanoate, iron naphthenate, iron octanoate or the like.

As the polyurethane resins used in the present invention, there can beexemplified known polyurethane resins or derivatives thereof asdescribed in Japanese Patent Publications (KOKOKU) Nos. 42-24194,46-7720, 46-10193 and 49-37839, and Japanese Patent ApplicationsLaid-Open (KOKAI) Nos. 50-123197, 53-126058 and 54-138098. Thederivatives of the polyurethane resins may include, for example,isocyanate-terminated urethane prepolymers or blocked compounds thereof(occasionally referred to as "Blocked isocyanate").

Examples of the polyisocyanates may include tolylene diisocyanate,phenylene diisocyanate, 4,4'-diphenyl methane diisocyanate,hexamethylene diisocyanate, xylylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, or the like. Among them,the preferred polyisocyanates are tolylene diisocyanate or isophoronediisocyanate.

Examples of the polyols may include polyether-polyols such aspolyoxyethylene glycol, polyoxypropylene glycol or polyoxytetramethyleneglycol; polyester-polyols such as polyethylene adipate, polyethylenebutylene adipate or polycaprolactone; acryl-based polyols; castor oil;or the like. Among them, the preferred polyols are polyoxyethyleneglycol, polyoxytetramethylene glycol or polyester-polyols. In general,there can be used polyols having a molecular weight of 300 to 2,000.

Examples of chain-lengthening agents or cross-linking agents may includeethylene glycol, propylene glycol, butane diol, diethylene glycol,trimethylol propane, hydrazine, ethylenediamine, diethylene triamine,4,4'-diamino-diphenyl methane, 4,4'-diamino-dicyclo-hexyl methane, wateror the like.

The afore-mentioned polyurethane resins preferably contain anionicsubstituent groups such as --SO₃ H, --OSO₃ H, --COOH, or ammonium salts,alkali metal salts or alkali earth metal salts of these substituentgroups in order to enhance a solubility thereof in a solvent comprisingmainly water. These polyurethane resins can be produced, for example, bythe below-mentioned methods (1) to (3).

(1) Production method in which compounds having anionic substituentgroups are used as the polyisocyanate, the polyol, the chain-lengtheningagent or the like:

For example, the polyisocyanate containing anionic substituent groupscan be produced by sulfonating an aromatic isocyanate compound. Inaddition, isocyanate compounds containing groups derived from sulfatesof amino alcohols or diamino-carboxylates can also be used for the abovepurpose.

(2) Production method in which a compound containing anionic substituentgroups is reacted with unreacted isocyanate groups of the producedpolyurethane:

As the compounds containing anionic substituent groups, there can beused those compounds containing groups derived from, for example,bisulfite, amino-sulfonic acid or salt thereof; amino-carboxylic acid orsalts thereof; sulfates of amino alcohol or salts thereof; hydroxyaceticacid or salts thereof; or the like.

(3) Production method in which an active hydrogen-containing group ofthe polyurethane such as --OH or --COOH is caused to react with aspecific compound:

As the specific compounds, there can be exemplified dicarboxylicanhydrides, tetracarboxylic anhydrides, sultone, lactone,epoxy-carboxylic acids, epoxy-sulfonic acid, 2,4-dioxo-oxazoline,isatoic anhydride, phostone or the like. Further, cyclic compoundshaving 3- to 7-membered ring, which contain a salt-type group such ascarbyl sulfate or a group capable of forming a salt after opening of thering, can also be used as the specific compounds.

The amino resins used in the present invention may include polymers orprepolymers which are obtained by reacting an amino compound or an amidocompound with an aldehyde, or derivatives thereof.

Examples of the amino compounds or amido compounds as a skeleton of theamino resin may include urea, thio urea, ethylene urea, dihydroxyethylene urea, triazones, melamine, iso-melamine, benzoguanamine, glycolureyl, acetoguanamine, guanyl melamine, dicyan-diamide, homopolymers ofdicyan-diamide, copolymers of dicyan-diamide, aminoacryl (acryl- ormethacryl-based monomers containing amino groups), homopolymers ofaminoacryl, copolymers of aminoacryl, aniline or the like. Among them,the preferred amino or amido compounds are urea, melamine,benzoguanamine or copolymers of aminoacryl. In addition, examples of thealdehydes used for the production of the amino resins may includeformaldehyde, glyoxal or the like. Among them, the preferred aldehydesare formaldehyde.

Examples of the polymers or prepolymers obtained by reacting the aminocompound or the amido compound with the aldehyde, may includemonomethylol urea, dimethylol urea, trimethylol urea, tetramethylolurea, methylene urea, methylol methylene urea, methylol methylene ureatrimer, monomethylol melamine, dimethylol melamine, trimethylolmelamine, tetramethylol melamine, pentamethylol melamine, hexamethylolmelamine, monomethylol benzoguanamine, dimethylol benzoguanamine,trimethylol benzoguanamine, tetramethylol benzoguanamine, monomethylolglycol ureyl, dimethylol glycol ureyl, trimethylol glycol ureyl,tetramethylol glycol ureyl, homopolymers of N-methylol acrylamide,copolymers of N-methylol acrylamide or the like. Some of these compoundsare occasionally called "methylol-added amino resins". Among them, thepreferred polymers or prepolymers are tetramethylol urea, trimethylolmelamine, tetramethylol melamine, pentamethylol melamine, hexamethylolmelamine or copolymers of N-methylol acrylamide.

Further, examples of the derivatives of the afore-mentioned polymers orprepolymers may include monomethoxy-methyl urea, monobutoxy-methyl urea,dimethoxy-methyl urea, dibutoxy-methyl urea, trimethoxy-methyl urea,tributoxy-methyl urea, tetramethoxy-methyl urea, tetrabuoxy-methyl urea,monomethoxy-methyl melamine, monobutoxy-methyl melamine,dimethoxy-methyl melamine, dibutoxy-methyl melamine, trimethoxy-methylmelamine, tributoxy-methyl melamine, tetramethoxy-methyl melamine,tetrabutoxy-methyl melamine, pentamethoxy-methyl melamine,pentabutoxy-methyl melamine, hexamethoxy-methyl melamine,hexabutoxy-methyl melamine, monomethoxy-methyl benzoguanamine,monobutoxy-methyl benzoguanamine, dimethoxy-methyl benzoguanamine,dibutoxy-methyl benzoguanamine, trimethoxy-methyl benzoguanamine,tributoxy-methyl benzoguanamine, tetramethoxy-methyl benzoguanamine,tetrabutoxy-methyl benzoguanamine, monomethoxy-methyl glycol ureyl,monobutoxy-methyl glycol ureyl, dimethoxy-methyl glycol ureyl,dibutoxy-methyl glycol ureyl, trimethoxy-methyl glycol ureyl,tributoxy-methyl glycol ureyl, tetramethoxy-methyl glycol ureyl,tetrabutoxy-methyl glycol ureyl, homopolymers of N-methoxy-methylacrylamide, copolymers of N-methoxy-methyl acrylamide, homopolymers ofN-butoxy-methyl acrylamide, copolymers of N-butoxy-methyl acrylamide orthe like. Some of these compounds are called "alkyl-etherified aminoresins". Among them, the preferred derivatives of the polymers orprepolymers are tetramethoxy-methyl urea, trimethoxy-methyl melamine,tributoxy-methyl melamine, tetramethoxy-methyl melamine,tetrabutoxy-methyl melamine, pentamethoxy-methyl melamine,pentabutoxy-methyl melamine, hexamethoxy-methyl melamine,hexabutoxy-methyl melamine or copolymers of N-methoxy-methyl acrylamide.

Incidentally, from the industrial viewpoint, compounds having anintermediate structure between the afore-mentioned compounds areincluded in categories of amino resins. As a matter of course, theseintermediate compounds can also be used as the amino resins in thepresent invention. As the industrially available amino resins, there canbe exemplified urea resins, melamine resins, benzoguanamine resins,glycol ureyl resin, co-condensation products thereof, co-condensationproduct of these resins with other resins (e.g., alkyd resins) such asamino alkyd resins, or the like. An example of the melamine resinsindustrially produced is a co-condensation product of melamine,formaldehyde and methanol (or butanol). Accordingly, various melamineresins can be produced by varying the ratio between melamine,formaldehyde and methanol (or butanol). In this case, methanol andbutanol may be used in combination.

The self-curing reaction of the amino resins and the reaction of theamino resins with the other functional groups can be accelerated byheating or by the presence of catalysts. As the useful catalysts, therecan be used inorganic or organic acids. Specific examples of theinorganic or organic acids may include phosphoric acid, hydrochloricacid, sulfuric acid, methane sulfonic acid, p-toluene sulfonic acid,dodecylbenzene sulfonic acid, dinonyl-naphthalene sulfonic acid,dinonyl-naphthalene disulfonic acid, partial salts of these acids,partial esterification products of these acid, ammonium salts of theseacids, amine salts of these acids or the like.

The epoxy resins used in the present invention may include compoundshaving an epoxy group in molecules thereof, prepolymers of thesecompounds and cured products of these compounds. A typical example ofthe epoxy resins is a condensate of epichlorohydrin and bisphenol A.Especially, a reaction product of a low-molecular weight polyol andepichlorohydrin is an epoxy resin showing an excellent water-solubility.However, in the present invention, it is not necessarily required thatthe epoxy resins used are water-soluble. For example,water-dispersion-type epoxy resins or solvent-soluble-type epoxy resinscan also be suitably used in the present invention.

Specific examples of the epoxy resins may include sorbitol polyglycidylether, sorbitan polyglycidyl ether, polyglycerol polyglycidyl ether,pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether,triglycidyl-tris(2-hydroxyethyl) isocyanurate, glycerol polyglycidylether, trimethylol propane polyglycidyl ether, resorcin diglycidylether, neopentylglycol diglycidyl ether, 1,6-hexane diol diglycidylether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidylether, propylene glycol diglycidyl ether, polypropylene glycoldiglycidyl ether, polytetramethylene glycol diglycidyl ether, adipicacid diglycidyl ether, ortho-phthalic acid diglycidyl ether,hydroquinone diglycidyl ether, bisphenol-S diglycidyl ether, glycidylterephthalate, diburomo-neopentyl glycol diglycidyl ether, or the like.Among them, the preferred epoxy resins are polyglycerol polyglycidylether, glycerol polyglycidyl ether or trimethylol propane polyglycidylether.

As the commercially available products of epoxy resin emulsions, therecan be exemplified "DENACOL EM-125", "DENACOL EX-1101", "DENACOLEX-1102" "DENACOL EM-1103" all produced by NAGASE KASEI KOGYO CO., LTD.,or the like.

The oxazoline resins (polymers of oxazoline compounds) used in thepresent invention mean polymers obtained by using at least one oxazolinecompound as a raw monomer, or polymers having at least one oxazolinering therein. Examples of the oxazoline compounds may include2-oxazoline compounds, 3-oxazoline compounds, 4-oxazoline compounds orthe like. Among them, 2-oxazoline compounds are preferable because theyshow a high reactivity and, therefore, are industrially put intopractice.

Vinyl oxazolines can be readily subjected to radical polymerization inthe presence of azo-isobutylonitrile (AIBN) or benzoyl peroxide (BPO) toproduce polymers having an oxazoline ring on a side chain thereof. Also,the vinyl oxazolines can produce similar polyvinyloxazolines whensubjected to an anionic polymerization in which a catalyst such asn-butyl lithium is used. On the other hand, when the vinyl oxazolinesare subjected to a cationic polymerization in which a catalyst such asoxazolium salts or trifluoromethane sulfonic acid is used, polymershaving acrylamide or methacrylamide group on a side chain thereof can beproduced.

The polymers having an oxazoline ring on the side chain thereof or thepolymers having an acrylyl or methacrylyl group on the side chainthereof can cause a cross-linking reaction between the side chains toproduce a cross-linked polymer. As a matter of course, in theafore-mentioned polymerization processes, monomers having no oxazolinering can be introduced to produce copolymers of the vinyl oxazolines.

Examples of the coupling agents used in the present invention mayinclude silicon-based coupling agents, titanium-based coupling agents,zirconium-based coupling agents, aluminum-based coupling agents,zirconium/aluminum-based coupling agents or derivatives thereof. Amongthem, the preferred coupling agents are silicon-based coupling agents ortitanium-based coupling agents.

As the silicon-based coupling agents, there can be exemplified so-calledsilane coupling agents, alkyl(phenyl)alkoxysilane,alkylsilicate(alkoxysilane), chlorosilane or the like. Among thesesilicon-based coupling agents, the silane coupling agents are preferred.The "silane coupling agent" generally means those compounds which haveorganic functional groups exhibiting an especially high reactivity oraffinity to organic polymers, among silane compounds having organicfunctional groups each bonded to a silicon atom through a carbon atom(carbon-functional silanes). In other words, the silane coupling agentsinclude such silane compounds having a reactive functional group such astypically an amino group, an epoxy group, a vinyl group, a methacrylgroup or a mercapto group, and a hydrolyzable group such as typically analkoxy group, e.g., a methoxy group, an ethoxy group and an isopropenoxygroup, which groups are bonded respectively to the silicon atom.

Specific examples of the silane coupling agents may includeγ-(2-aminoethyl)aminopropyl-trimethoxy silane,γ-(2-aminoethyl)aminopropyl-methyldimethoxy silane,γ-methacryloxypropyl-trimethoxy silane, a salt of hydrochloric acid andN-β-(N-vinylbenzyl-aminoethyl)-γ-aminopropyl-trimethoxy silane,γ-glycidoxypropyl-trimethoxy silane, γ-mercaptopropyl-trimethoxy silane,vinyl-triacetoxy silane, γ-chloropropyl-trimethoxy silane,γ-anilinopropyl-trimethoxy silane, vinyl-trimethoxy silane,octadecyl-dimethyl 3-(trimethoxysilyl)propyl!ammonium chloride,γ-chloropropylmethyl-dimethoxy silane, γ-mercaptopropylmethyl-dimethoxysilane, vinyl-tris(β-methoxyethoxy) silane,β-(3,4-epoxycyclohexyl)ethyl-trimethoxy silane, ureid-propyl-trimethoxysilane, triaminopropyl trimethoxy silane,γ-4,5-dihydro-imidazole-propyl-trimethoxy silane,γ-cyanopropyl-trimethoxy silane, or the like.

Many of the afore-mentioned compounds are so-called three-functionalsilane coupling agents having three hydrolyzable groups such astypically alkoxy groups, which are bonded to the silicon atom. However,in the present invention, such compounds having not more than two alkoxygroups bonded to the silicon atom can also be usefully used as thesilane coupling agent. In addition, reaction products of theafore-mentioned compounds, for example, oligomers as condensates of theafore-mentioned compounds or reaction products of the afore-mentionedcompounds with polyvinyl alcohol or the like can also be effectivelyused as the silane coupling agent. Further, so-called polymer-typesilane coupling agents can also be used in the present invention.

The "polymer-type silane coupling agents" are compounds having both thereactive functional group and the hydrolyzable group such as typicallyan alkoxy group on the side chain of poly-dimethyl siloxane. Specificexamples of the polymer-type silane coupling agents may include "MAC2101", (Tradename) produced by NIPPON UNIKER CO., LTD. (poly-dimethylsiloxane containing an alkoxy group, an epoxy group and a polyethergroup), "MAC 2301", (Tradename) produced by NIPPON UNIKER CO., LTD.(poly-dimethyl siloxane containing an alkoxy group, a hydroxy group anda polyether group), or the like.

As the titanium-based coupling agents, there can be exemplifiedso-called usual titanium coupling agents, alkyl titanate, titaniumchelate compounds or the like. Among them, the titanium coupling agentsare preferred.

Examples of the titanium coupling agents may includeisopropyl-tri-isostearoyl titanate, isopropyl-tridodecylbenzene-sulfonyltitanate, isopropyl-tris(dioctyl-pyrophosphate)-titanate,tetra-isopropyl-bis (dioctyl-phosphite)-titanate, tetra-octyl-bis(di-tridecyl-phosphite)-titanate, tetra(2,2-diallyloxy-methyl-1-butyl-bis(di-tridecyl-phosphite)-titanate,bis(dioctyl-pyrophosphate)-oxy-acetate titanate,bis(dioctyl-pyrophosphate)-ethylene titanate, isopropyl-trioctanoyltitanate, isopropyl-dimethacryl-isostearyl titanate,isopropyl-isostearoyl-diacryl titanate, isopropyl-tri(dioctylphosphate)-titanate, isopropyl-tricumylphenyl titanate,isopropyl-tri(N-amidoethyl-aminoethyl)-titanate,dicumylphenyl-oxy-acetate titanate, di-isostearoyl-ethylene titanate orthe like.

As the zirconium-based coupling agents, there can be used alkylzirconates, zirconium chelate compounds or the like. Examples of thealkyl zirconates may include zirconium butyrate, zirconium acetylacetonate, acetyl acetone zirconium butyrate, zirconium lactate,zirconium stearate butyrate or the like. Examples of the zirconiumchelate compounds may include zirconium di-isopropoxide-dimethylacetoacetate or the like.

As the aluminum-based coupling agents, there can be used alkylaluminates, aluminum chelate compounds or the like. Examples of thealkyl aluminates which is "aluminum acid ester" may include trimethoxyaluminum, triethoxy aluminum, tri-isopropoxy aluminum, tri-benzyl alkoxyaluminum or the like. Examples of the aluminum chelate compounds mayinclude aluminum-di-n-butoxide-mono-ethyl acetoacetonate,aluminum-di-n-butoxide-mono-methyl aceroacetonate,aluminum-di-isobutoxide-mono-methyl acetoacetonate,aluminum-di-sec-butoxide-mono-ethyl acetoacetonate,aluminum-di-isopropoxide-mono-ethyl acetoacetonate or the like.

As the zirconium/aluminum-based coupling agents, so-calledzircoaluminate coupling agents can be exemplified. The zircoaluminatecoupling agents are reactive compounds containing zirconium andaluminum. Examples of the commercially available products of thezircoaluminate coupling agents may include "CAVCO MOD A", "CAVCO MOD C","CAVCO MOD C-1", "CAVCO MOD F", "CAVCO MOD M", "CAVCO MOD S", "CAVCO MODAPG", "CAVCO MOD CPG", "CAVCO MOD CPM", "CAVCO MOD FPM", "CAVCO MOD MPG"and "CAVCO MOD MPM" (Tradenames) all produced by CAVEDON CHEMICAL CO.,INC., or the like.

As the derivatives of the coupling agents, there can be exemplified atleast partially hydrolyzed products of the afore-mentioned compounds,condensates containing at least one of these compounds and thehydrolyzates thereof, reaction products of these compounds with othercompounds, e.g., a reaction product of polyvinyl alcohol with thepartially-hydrolyzed product of the silane coupling agent, or the like.

In accordance with the present invention, the coating layer formed onthe polyester base film may contain various other compounds in additionto the afore-mentioned compounds. Examples of the other compounds mayinclude binder polymers except for those mentioned above, cross-linkingagents except for those mentioned above, fillers or particles, waxes,anti-static agents, surfactants, anti-foaming agents, coatingproperty-improving agents, thickening agents, anti-oxidants, ultravioletlight absorbers, foaming agents, dyes, pigments or the like. The contentof the other compound is generally not more than 50% by weight based onthe total weight of the coating layer.

The coating solution used for forming the coating layer of the presentinvention is preferably an aqueous solution using water as a solventfrom the standpoint of safety and hygiene, but it may contain an organicsolvent as an assistant for water-soluble or water-dispersible resins.Further, a coating solution prepared by using an organic solvent solelycan also be used in the present invention. In the case where the solventmainly comprises water, the coating solution may be produced by forciblydispersing the afore-mentioned compounds in water. However, it ispreferred that the coating solution is of a self-dispersion type fromthe standpoint of dispersion stability thereof.

The self-dispersion-type coating solution can be prepared from a coatingmaterial comprising the afore-mentioned compounds into which hydrophilicgroups are introduced. Examples of the hydrophilic groups introduced mayinclude nonionic groups such as a hydroxyl group or a polyether group,anionic groups such as groups derived from sulfonic acid, carboxylicacid phosphoric acid or salts thereof, and cationic groups such as oniumsalts, e.g., quaternary ammonium salts. As the methods for introducingthe hydrophilic groups into the compounds, there can be adopted variouscopolymerization reactions including graft polymerization or the like.

Among the afore-mentioned coating materials, water-soluble orwater-dispersible coating materials containing anionic groups areespecially preferable. The lower limit of content of the anionic groupsin the coating material is generally 0.05% by weight from the standpointof imparting water-solubility or water-dispersibility thereto. On theother hand, the upper limit of content of the anionic groups in thecoating material is not particularly restricted. However, in the casewhere the coating material comprises polyester, the upper limit ofcontent of the anionic groups in the coating material is preferably 15%by weight from the standpoint of producing a high-molecular weightpolyester having a sufficient film strength. Incidentally, the "content"of the anionic groups in the coating material means a weight percentageof anionic radicals excluding counter ions relative to the compoundconstituting the coating material.

The methods of applying the coating solution prepared from theafore-mentioned coating material onto the polyester film as a base filmmay include, for example, those using a reverse-roll coater, a gravurecoater, a rod coater, an air-doctor coater or other coating devices asdescribed in Yuji HARASAKI, "Coating System" published by MAKI SHOTEN,1979.

In accordance with the present invention, the coating layer ispreferably formed by an in-line coating method. The in-line coatingmethod comprises applying the coating solution onto a polyester filmduring the production of the polyester film. More specifically, thecoating solution can be applied onto the polyester film at an optionalstage between melt-extrusion of a raw polyester material and winding-upof resultant films which have been biaxially stretched and thenheat-set. In general, the coating solution can be applied onto any of asubstantially amorphous unstretched sheet obtained by rapidly coolingthe melt-extruded polyester, a uniaxially-stretched film obtained bystretching the unstretched film in the longitudinal direction thereof,and a biaxially-stretched film before heat-setting. Among them, themethod of applying the coating solution onto the uniaxially-stretchedfilm and then stretching the film in the transverse direction thereof ispreferred. Such a method is advantageous in production cost, because theproduction of the polyester film can be conducted simultaneously withthe coating and drying of the coating solution. In addition, in theafore-mentioned method, since the polyester film is stretched afterapplying the coating material thereto, the resultant coating layer canbe readily formed into a thin film. Further, since the polyester filmonto which the coating layer has been formed can be subjected to such ahigh-temperature heat-treatment which cannot be achieved by the othermethods, the resultant coating layer and the polyester film are firmlybonded to each other.

The thickness of the coating layer after drying is generally in therange of 0.001 to 10 μm, preferably 0.010 to 5 μm, more preferably 0.015to 2 μm. When the thickness of the coating layer is less than 0.001 μm,the polyester film for decorative plate or decorative sheet may not besufficiently adhered to the substrate. On the other hand, when thethickness of the coating layer is more than 10 μm, the coating layer mayact like an adhesive, so that the film rolled up may tend to suffer fromso-called blocking, thereby causing portions of the rolled-up film to bebonded to each other.

When the polyester film for decorative plate or decorative sheetaccording to the present invention is laminated onto the substrate, anoptional adhesive can be used for the adhesion therebetween. Examples ofthe adhesives may include urea resin-based adhesives, melamineresin-based adhesives, phenol resin-based adhesives, α-olefinresin-based adhesives, adhesives comprising a mixture of a water-solublepolymer and isocyanate, epoxy-based adhesives, solvent-type vinylacetate resin-based adhesives, emulsion-type vinyl acetate resin-basedadhesives, acryl emulsion-type adhesives, hot-melt adhesives,cyanoacrylate-based adhesives, polyurethane-based adhesives, chloroprenerubber-based adhesives, nitrile rubber-based adhesives, SBR-basedadhesives, modified rubber emulsion-based adhesives, ethylene copolymerresin-based adhesives, resorcin-based adhesives, natural rubber-basedadhesives, cellulose-based adhesives, starch glue, dextrin or the like.

In the case where the substrate comprises a wood material, in order toadhere the polyester film to such a substrate, there can be mainly usedurea resin-based adhesives, melamine resin-based adhesives, α-olefinresin-based adhesives, adhesives comprising a mixture of a water-solublepolymer and isocyanate, emulsion-type vinyl acetate resin-basedadhesives, acryl emulsion-type adhesives, chloroprene rubber-basedadhesives, modified rubber emulsion-based adhesives or cellulose-basedadhesives.

Examples of the commercially-available products of the urea resin-basedadhesives may include "UROID 310", "UROID 320", "UROID 701", "UROID 755"or "UROID 730" all produced by MITSUI TOATSU CHEMICAL CO., LTD., or thelike. Examples of the commercially-available products of the melamineresin-based adhesives may include melamine/urea resin-type adhesivessuch as "UROID 350", "UROID 775", "UROID 781", "STRUCTBOND C-1" or"STRUCTBOND C-10" all produced by MITSUI TOATSU CHEMICAL CO., LTD.,melamine/phenol resin-type adhesives such as "UROID 883" or "UROID 811"both produced by MITSUI TOATSU CHEMICAL CO., LTD., or the like.

Examples of the commercially-available products of the phenolresin-based adhesives may include "UROID PL-261", "UROID PL-281", "UROIDPL-211" or "UROID PL-222" all produced by MITSUI TOATSU CHEMICAL CO.,LTD., "PR22" produced by KONISHI CO., LTD., or the like. Examples of thecommercially-available products of the α-olefin resin-based adhesivesmay include "SH2", "SH3", "SH5W", "SH6", "SH20" or "SH20L2" all producedby KONISHI CO., LTD., or the like. Examples of thecommercially-available products of the adhesives comprising a mixture ofwater-soluble polymer and isocyanate may include "CU1", "CU5" or "CU51"all produced by KONISHI CO., LTD., or the like.

Examples of the commercially-available products of the epoxy resin-basedadhesives may include "S-DEIN 3008", "S-DEIN 3200", "S-DEIN 3710","S-DEIN 3730", "S-DEIN 3740", "S-DEIN 3750", "S-DEIN 3600", "S-DEIN3611" or "S-DEIN 3450" all produced by SEKISUI CHEMICAL INDUSTRY CO.,LTD., or the like. Examples of the commercially-available products ofthe solvent-type vinyl acetate resin-based adhesives may include "S-DEIN1011", "S-DEIN 1013", "S-DEIN 1015", "S-DEIN 1020" or "S-DEIN 1057" allproduced by SEKISUI CHEMICAL INDUSTRY CO., LTD., or the like.

Examples of the commercially-available products of the emulsion-typevinyl acetate resin-based adhesives may include "656", "605", "EM-65","EM-90" or "60-2(T)" all produced by CEMEDEIN CO., LTD., "S-DEIN 5100","S-DEIN 5165", "S-DEIN 5200", "S-DEIN 5300", "S-DEIN 5301", "S-DEIN5320", "S-DEIN 5400", "S-DEIN 5403", "S-DEIN 5405", "S-DEIN 5406","S-DEIN 5408", "S-DEIN 5410", "S-DEIN 5440", "S-DEIN 5500", "S-DEIN5700", "S-DEIN 5800", "S-DEIN 5803" or "S-DEIN 5815" all produced bySEKISUI CHEMICAL INDUSTRY CO., LTD., "CH2", "CH2W", "CH3", "CH5","CH18", "CH20", "CH7", "CH7L", "CH27", "CH1000", "CH63", "CH65","CH131", "CH133", "CH115", "CX10", "CX55", "CH1500", "CH1600","CH3000L", "CH72", "CH73", "CH74", "CH77", "CH107 with a curing agent","PTS(A/B)" or "CH7000/PTS7000" all produced by KONISHI CO., LTD., or thelike.

Examples of the commercially-available products of the acrylemulsion-based adhesives may include "EM-315", "EM-370A.B","MORCORN-685", "EM-326", "679" or "EM-702(new)" all produced by CEMEDEINCO., LTD., "CEL10", "CEL20", "CEL22", "CEL25N", "CEL60", "CEL63","CVC33", "CVC36", "CVC36F", "CV3105 series", "SP65", "SP85", "SP200","SP210", "SP220", "SP281", "SP285", "SP290", "SP291", "SP3055", "CN520","CZ100", "CZ220", "CE780", "CE801", "NEDABOND A" or "NEDABOND W1000" allproduced by KONISHI CO., or the like.

Examples of the commercially-available products of the chloroprenerubber-based adhesives may include "S-DEIN 276AL", "S-DEIN 276FS","S-DEIN 276M", "S-DEIN SG202D", "S-DEIN 278", or "S-DEIN SG2005E" allproduced by SEKISUI CHEMICAL INDUSTRY, CO., LTD., "G10", "G11", "G12","SUPER-G ACE", "G17", "G18", "G19", "G5000", "G5800", "GS5", "GU55BLUE", "GU68-F GREEN", "G77", "G78", "NEDABOND-G", "SUPER-G SPRAY" or"GW150" all produced by KONISHI CO., LTD., or the like.

Examples of the commercially-available products of the modified rubberemulsion-based adhesives may include "CL-5N" or "CL-7N" both produced byCEMEDEIN CO., LTD., "FL200", "FL105S", "HB2" or "HB10" all produced byKONISHI CO., LTD., or the like. Examples of the commercially-availableproducts of the resorcin-based adhesives may include "KR15" produced byKONISHI CO., LTD., or the like. Examples of the commercially-availableproducts of the cellulose-based adhesives may include "WORKING BOND(K)"produced by KONISHI CO., LTD., or the like.

As mentioned above, in accordance with the present invention, there canbe provided the polyester film for decorative plate or decorative sheet,which is free from environmental pollution upon burning such asincineration and adverse influence by the color tone of the substrate,and which is capable of producing a picture pattern having a high designvalue and excellent in dimensional stability and adhesion to thesubstrate.

Further, in accordance with the present invention, there is alsoprovided the film for decorative plate laminated by clear film, whichcan be considerably improved in suitability for V-cut processing, inresistance to impact deformation and in adhesive property, and which isfree from environmental pollution upon burning such as incineration.

EXAMPLES

The present invention is described in more detail below by way ofexamples, but these examples are not intended to limit the presentinvention, and various modifications and changes thereof can be achievedwithout departing from the scope of the present invention. Incidentally,unless otherwise specified, "parts" and "%" used in the followingExamples and Comparative Examples represent "parts by weight" and "% byweight", respectively.

The measuring methods used in the following Examples and ComparativeExamples are as follows.

(1) Optical Density (Hiding Power)

The optical density of the polyester film has been determined bymeasuring an intensity of light transmitted through a G filter by aMacbeth illuminometer (TD-904 Model). It is indicated that the largerthe optical density is, the higher the hiding power becomes.

(2) Heat Shrinkage Percentage

A sample film having a width of 25 mm and a length of 1.0 m was placedin a circulating hot air oven (manufactured by TABAIESPECK CO., LTD.)and subjected to free end-heat treatment at 100° C. for 5 minutes. Theratio of longitudinal dimension of the sample film after theheat-treatment to that before the heat-treatment was represented by %.

(4) Suitability for Decorative Sheet

A decorative sheet was adhered to a plywood, which was a black flatsurface substrate, by using an ethylene/vinyl acetate-based adhesive("CVC-36", produced by KONICA CO., LTD.) as an adhesive to prepare adecorative plate. A picture pattern printed on a surface of thedecorative sheet were observed to determine whether or not the picturepattern suffered from any change in color tones and any deterioration indesign value. The results of the observation were classified into thefollowing three ranks:

∘: Printed picture pattern were kept in a good condition without anydeterioration in its design value.

X: Considerable change in color tone of the printed picture pattern andconsiderable deterioration in design value thereof were caused.

Δ: Picture pattern were in an intermediate condition between the abovetwo ranks.

Further, the decorative plate was placed in a circulating hot air oven(manufactured by TABAIESPECK CO., LTD.),and heat-treated at 180° C. for5 minutes. The heat-treated decorative sheet was then observed withrespect to its surface condition. The results of the observation wereclassified into the following two ranks:

∘: Decorative sheet was kept in a good surface condition without anychange.

X: Wrinkles or shrinkage were caused on the surface of the decorativesheet.

Furthermore, a surface of another decorative sheet was embossed at 150°C. with a roll having protrusions on a surface thereof. The results wereclassified into the following ranks:

⊚: The embossing was especially easy to perform.

∘: The embossing was readily performed.

X: The embossing was difficult to perform.

(7) Adhesion Property

The adhesion of the polyester film produced according to the presentinvention to plywood was measured and evaluated by the below-mentionedtesting methods. Samples to be measured were prepared as follows. First,an adhesive was uniformly coated on the plywood in an amount of 110 g/m²in wet condition. Next, the polyester film was superimposed and adheredover the plywood coated with the adhesive such that its surface to beevaluated faces toward the adhesive on the plywood. The thus-obtainedsample was allowed to stand for one hour while applying a pressure of 2kg/cm² thereto by a pressing machine. Thereafter, the sample was removedfrom the pressing machine and allowed to stand for one day at roomtemperature. Using the thus-obtained sample, the adhesion property ofthe polyester film was evaluated in the following manner.

(7-1) Manual Peeling Test

The polyester film of the sample was manually peeled from the plywood tovisually observe the peeled surfaces thereof. The results of theobservation were classified into the following ranks:

∘: The plywood underwent ply-separation;

X: The polyester film and the plywood were separated from each other atthe boundary surface therebetween; and

Δ: Both the afore-mentioned conditions were caused simultaneously.

In accordance with the present invention, the polyester films classifiedinto either of the ranks "∘" and "Δ" are suitable.

(7-2) High-temperature Creep Peeling Test

Cut lines were formed at-intervals of 1 cm on the polyester film. Thepolyester film was partially peeled from the plywood along the cutlines. Thereafter, the plywood was fixedly held in the horizontaldirection such that the partially peeled polyester film was verticallysuspended downward from the plywood. A load of 500 g was applied to anend of the suspended portion of the polyester film. While maintainingthat condition, the plywood and the polyester film were then allowed tostand at 60° C. within a dry hot air oven. After one hour, the length ofthe polyester film further stripped from the plywood by applying theload thereto was measured. The results of the measurement wereclassified into the following ranks:

⊚: The length of the polyester film further stripped after one hour wasless than 2 mm;

∘: The length of the polyester film further stripped after one hour wasless than 5 mm;

Δ: The length of the polyester film further stripped after one hour wasnot less than 5 mm and less than 20 mm; and

X: The length of the polyester film further stripped after one hour wasnot less than 20 mm.

In accordance with the present invention, the polyester films classifiedinto either of the ranks "⊚" and "∘" are suitable.

In the afore-mentioned peeling tests, five kinds of adhesives shown inTable 1 below were used. The adhesive property of the polyester filmtested was evaluated by an average of five measured values which wererespectively obtained by using the five kinds of adhesives.

                  TABLE 1    ______________________________________    Kind of adhesive Product used    ______________________________________    Emulsion-type vinyl acetate-                     "605" produced by CEMEDEIN    based adhesive   CO., LTD.    Emulsion-type vinyl acetate-                     "CH18" produced by KONISHI    based adhesive   CO., LTD.    Acryl emulsion-based adhesive                     "679" produced by CEMEDEIN                     CO., LTD.    Acryl emulsion-based adhesive                     "CVC36" produced by KONISHI                     CO., LTD.    Rubber-based adhesive                     "G17" produced by KONISHI                     CO., LTD.    ______________________________________

Production Example 1

100 parts of dimethyl terephthalate, 70 parts of ethylene glycol and0.07 part of calcium acetate monohydrate were placed in a reactionvessel and heated to distill off methanol and conduct an ester exchangereaction therebetween. After about 4.5 hours from the initiation of thereaction, the temperature of the reaction mixture was reached to 230°C., upon which the ester-exchange reaction was substantially terminated.

Next, 0.04 part of phosphoric acid and 0.035 part of antimonytrichloride were added to the reaction mixture. The resultant reactionmixture was then subjected to polymerization according to an ordinarymethod. Specifically, the temperature of the reaction mixture wasgradually elevated up to a final temperature of 280° C., during whichthe pressure in the reaction vessel was gradually reduced to a finalpressure of 0.05 mmHg. After 4 hours, the reaction was terminated andthe reaction product was chipped by an ordinary method to obtain apolyester (A). 40 parts of the thus-obtained polyester (A) and 60 partsof rutile titanium dioxide were molten and mixed together in atwin-screw extruder by an ordinary method. Thereafter, the resultantmixture was chipped to obtain master batch polyester chips (B).

88 parts of the polyester chips (A) and 12 parts of the polyester chips(B) were separately dried at 180° C. for 5 hours and then mixedtogether. The obtained mixture was molten and extruded according to anordinary method, and rapidly cooled and solidified. The extrudedmaterial (sheet) was in turn biaxially stretched 2.9 times in thelongitudinal direction at 83° C. and 3.2 times at 125° C. in thetransverse direction, respectively, and then heat-treated at 210° C., sothat a biaxially stretched polyester film (I) having a thickness of 38μm was obtained.

Production Example 2

The same procedure as in Example 1 was conducted except that a polyesterchips (C) were used instead of the polyester chips (B), wherein upon theproduction of the polyester chips (B), 3.5 parts of anthraquinone as ayellow pigment, 0.1 part of carbon black and 2.0 parts of iron oxide inaddition to 40 parts of the polyester (A) and 60 parts of rutiletitanium dioxide, were blended together, the resultant mixture wasmolten and intimately mixed together in a twin-screw extruder, and thenchipped to produce master batch polyester chips (C), thereby obtaining abiaxially stretched polyester film (II).

Production Example 3

The same procedure as in Example 1 was conducted except that thepolyester film was produced from the composition composed of 4 parts ofthe polyester chips (B), 13 parts of polyolefin and 83 parts of thepolyester chips (A), thereby obtaining a biaxially stretched polyesterfilm (III).

Comparative Example 1

The same procedure as in Production Example 1 was conducted except thatthe amount of the polyester chip (B) blended was changed to one part, toproduce a biaxially-stretched polyester film (IV). The properties of thethus-obtained polyester film (IV) are shown from Table 5. As seen inTable 5, the polyester film (IV) was unsatisfactory in suitability fordecorative plate, i.e., deteriorated in not only adhesive property butalso other properties.

Comparative Example 2

The same procedure as in Production Example 1 was conducted except thatthe film formation was conducted such that the resultant polyester filmshowed a heat-shrinkage coefficient of 15%, to produce abiaxially-stretched polyester film (V). The properties of thethus-obtained polyester film (V) are shown in Table 5. As seen fromTable 5, the polyester film (V) was unsatisfactory in suitability fordecorative plate, i.e., deteriorated in not only adhesion property butalso other properties.

Example 1

A biaxially-stretched polyester film provided with a coating layer wasproduced. The combination of the coating layer and a base film used forthe production of the polyester film is shown in Table 2. That is, acoating layer 1 was formed on one surface of the polyester film (I)produced in Production Example 1. The composition of the coating layer 1is shown in Table 3. Specifically, the coating material for the coatinglayer 1 was prepared by mixing the raw coating materials A and Jtogether in a weight ratio of 95/5 in terms of dry solid contentthereof. The mixture of the raw coating materials A and B was dilutedwith water, if required, and coated on the base film by a bar coater.The thickness of the coating layer 1 after drying was 0.3 μm. Thecomponents of the respective coating materials are shown in Table 4.Specifically, the raw coating material A was an aqueous dispersion ofpolyester, and the raw coating material J was an aqueous dispersion ofsilicon oxide. Incidentally, it should be noted that while the rawcoating materials as shown in Table 4 were composed mainly of theaqueous dispersion, the compositions of the coating layers as shown inTable 3 were based on dry solid contents of the respective raw coatingmaterials, i.e., based on the weights of the raw coating materials fromwhich water content was removed. The properties of the thus-obtainedcoated polyester film are shown in Table 5. As seen from Table 5, theobtained coated polyester film was satisfactory in suitability fordecorative plates including the adhesion property thereof. Incidentally,the adhesion property of the polyester film was evaluated with respectto a surface thereof on which the coating layer is formed.

Example 2

The same procedure as in Example 1 was conducted except that thepolyester film (II) obtained in Production Example 2 was used as a basefilm, to produce a coated polyester film. The properties of thethus-produced coated polyester film are shown in Table 5. As seen fromTable 5, the coated polyester film was satisfactory in suitability fordecorative plate including the adhesion property thereof.

Example 3

The same procedure as in Example 1 was conducted except that thepolyester film (III) obtained in Production Example 3 was used as a basefilm, to produce a coated polyester film. The properties of thethus-produced coated polyester film are shown in Table 5. As seen fromTable 5, the coated polyester film was satisfactory in suitability fordecorative plate including the adhesion property thereof.

Comparative Example 3

The same procedure as in Example 1 was conducted except that thepolyester film (IV) obtained in Comparative Example 1 was used as a basefilm, to produce a coated polyester film. The properties of thethus-produced coated polyester film are shown in Table 5. As seen fromTable 5, with respect to the suitability for decorative plate, thecoated polyester film was satisfactory only in adhesion property thereofbut unsatisfactory in other properties thereof.

Comparative Example 4

The same procedure as in Example 1 was conducted except that thepolyester film (V) obtained in Comparative Example 2 was used as a basefilm, to produce a coated polyester film. The properties of thethus-produced coated polyester film are shown in Table 5. As seen fromTable 5, with respect to the suitability for decorative plate, thecoated polyester film was satisfactory only in adhesion property thereofbut unsatisfactory in other properties thereof.

Examples 4 to 7

The same procedure as in Example 2 was conducted except that thecompositions of coating layers were varied as shown in Tables 2, 3 and4, to produce coated polyester films. The properties of thethus-produced coated polyester films are shown in Table 5. All of thecoated polyester films were satisfactory in suitability for decorativeplate including the adhesion property thereof.

Examples 8

The coating solution was applied onto the polyester film as a base filmwhile the polyester film was biaxially stretched in turn in thelongitudinal and transverse directions. Specifically, after thepolyester film was stretched 2.9 times its initial dimension in thelongitudinal direction at 83° C., the coating solution was applied toone surface of the longitudinally stretched polyester film, which wasthen stretched 3.2 times its initial dimension in the transversedirection at 125° C.. The procedure of Production Example 1 other thanthe afore-mentioned stretching and coating process was followed toproduce a coated polyester film. That is, the coating solution wasprepared by mixing the raw coating materials A and J together and, ifnecessary, diluting the mixture with water to adjust the weight ratio ofA:J to 95:5 in terms of dry solid contents thereof. The thus-preparedcoating solution was applied onto the polyester film by a roll coater.The detailed composition of the obtained coating layer are shown inTables 2, 3 and 4. The properties of the obtained coated polyester filmare shown in Table 5. As seen from Table 5, the coated polyester filmwas satisfactory in suitability for decorative plate including theadhesion property thereof. The coated polyester film obtained in thisExample showed a good adhesion property, notwithstanding the filmthickness thereof was as small as one third of that of Example 1. Inaddition, the polyester film of this Example had an extremely excellentsliding property, thereby enabling smooth lamination thereof over theplywood. It was considered that these effects were obtained by using thein-line coating method.

Examples 9 to 22

The coated polyester films were produced by in-line coating method inthe same manner as in Example 8 except that the combination of thecoating layer and the base film used were varied as shown in Table 2.The detailed composition of the thus-formed coating layers are shown inTables 2, 3 and 4. The properties of the obtained coated polyester filmsare shown in Table 5. As seen from Table 5, the coated polyester filmswere satisfactory in suitability for decorative plate including theadhesion property thereof. All of the coated polyester films obtained inExamples 9 to 22 showed a good adhesion property, not withstanding thefilm thicknesses thereof were as small as one third of those of Examples1 to 7. In addition, these coated polyester films had an extremelyexcellent sliding property, thereby enabling smooth lamination thereofover the plywood. It was considered that these effects were obtained byusing the in-line coating method.

Examples 23 to 46

The coated polyester films were produced by in-line coating method inthe same manner as in Example 9 except that the combination of thecoating layer and the base film used were varied as shown in Table 2.Specifically, all the base films used were composed of the polyesterfilm (II). The coating solution was applied on the base films afterlongitudinal stretching but before transverse stretching. The detailedcomposition of the thus-formed coating layers are shown in Tables 2, 3and 4. The properties of the obtained coated polyester films are shownin Table 5. As seen from Table 5, the coated polyester films weresatisfactory in suitability for decorative plate including the adhesionproperty thereof. Especially in the case where the coating layerscontained a cross-linkable component, the resultant coated polyesterfilms were able to frequently exhibit a high adhesion property even atan elevated temperature.

                  TABLE 2    ______________________________________    Coating Base film    layer   I        II       III    IV     V    ______________________________________    None    --       --       --     Com-   Com-                                     para-  para-                                     tive   tive                                     Exam-  Exam-                                     ple 1  ple 2    Coating Exam-    Exam-    Exam-  Com-   Com-    layer 1 ple 1    ple 2    ple 3  para-  para-                                     tive   tive                                     Exam-  Exam-                                     ple 3  ple 4    Coating --       Exam-    --     --     --    layer 2          ple 4    Coating --       Exam-    --     --     --    layer 3          ple 5    Coating --       Exam-    --     --     --    layer 4          ple 6    Coating --       Exam-    --     --     --    layer 5          ple 7    Coating Exam-    Exam-    Exam-  --     --    layer 6 ple 8    ple 9    ple 10    Coating Exam-    Exam-    Exam-  --     --    layer 7 ple 11   ple 12   ple 13    Coating Exam-    Exam-    Exam-  --     --    layer 8 ple 14   ple 15   ple 16    Coating Exam-    Exam-    Exam-  --     --    layer 9 ple 17   ple 18   ple 19    Coating Exam-    Exam-    Exam-  --     --    layer 10            ple 20   ple 21   ple 22    Coating --       Exam-    --     --     --    layer 11         ple 23    Coating --       Exam-    --     --     --    layer 12         ple 24    Coating --       Exam-    --     --     --    layer 13         ple 25    Coating --       Exam-    --     --     --    layer 14         ple 26    Coating --       Exam-    --     --     --    layer 15         ple 27    Coating --       Exam-    --     --     --    layer 16         ple 28    Coating --       Exam-    --     --     --    layer 17         ple 29    Coating --       Exam-    --     --     --    layer 18         ple 30    Coating --       Exam-    --     --     --    layer 19         ple 31    Coating --       Exam-    --     --     --    layer 20         ple 32    Coating --       Exam-    --     --     --    layer 21         ple 33    Coating --       Exam-    --     --     --    layer 22         ple 34    Coating --       Exam-    --     --     --    layer 23         ple 35    Coating --       Exam-    --     --     --    layer 24         ple 36    Coating --       Exam-    --     --     --    layer 25         ple 37    Coating --       Exam-    --     --     --    layer 26         ple 38    Coating --       Exam-    --     --     --    layer 27         ple 39    Coating --       Exam-    --     --     --    layer 28         ple 40    Coating --       Exam-    --     --     --    layer 29         ple 41    Coating --       Exam-    --     --     --    layer 30         ple 42    Coating --       Exam-    --     --     --    layer 31         ple 43    Coating --       Exam-    --     --     --    layer 32         ple 44    Coating --       Exam-    --     --     --    layer 33         ple 45    Coating --       Exam-    --     --     --    layer 34         ple 46    ______________________________________

                  TABLE 3    ______________________________________     Composition and thickness of coating layer!               Composition of coating    Number of  layer (dry solid                              layer thickness    coating layer               content: wt. %)                              (μm)    ______________________________________    1          A/J = 95/5     0.3    2          B/J = 95/5     0.3    3          C/J = 95/5     0.3    4          D/J = 95/5     0.3    5          E/B/J = 85/10/5                              0.3    6          A/J = 95/5     0.1    7          B/J = 95/5     0.1    8          C/J = 95/5     0.1    9          D/J = 95/5     0.1    10         E/B/J = 85/10/5                              0.1    11         H/J = 95/5     0.1    12         A/F = 90/10    0.1    13         B/F = 90/10    0.1    14         C/F = 90/10    0.1    15         C/A/F/J = 65/20/10/5                              0.1    16         B/A/F/J = 65/20/10/5                              0.1    17         A/B/F/J = 65/20/10/5                              0.1    18         A/E = 90/10    0.1    19         B/E = 90/10    0.1    20         C/E = 90/10    0.1    21         C/A/E/J = 65/20/10/5                              0.1    22         B/A/E/J = 65/20/10/5                              0.1    23         A/B/E/J = 65/20/10/5                              0.1    24         A/H = 90/10    0.1    25         B/H = 90/10    0.1    26         C/H = 90/10    0.1    27         C/A/H/J = 65/20/10/5                              0.1    28         B/A/H/J = 65/20/10/5                              0.1    29         A/B/H/J = 65/20/10/5                              0.1    30         A/I = 80/20    0.1    31         C/I = 80/20    0.1    32         A/G = 80/20    0.1    33         B/G = 80/20    0.1    34         C/G = 80/20    0.1    ______________________________________

                  TABLE 4    ______________________________________     Composition of Raw Coating Materiel!    Raw coating    material Composition    ______________________________________    A        Aqueous dispersion of polyester resin (aqueous             dispersion containing polyester obtained by             polymerizing the below-mentioned components at             the below-mentioned molar ratio):             Terephthalic acid/5-sodium-sulfo-isophthalic             acid/ethylene glycol/diethylene glycol             = 92/8/77/23 mole %    B        Aqueous dispersion of acrylic resin (emulsion             polymer obtained by polymerizing the below-             mentioned components at the below-mentioned             molar ratio):             Methyl methacrylate/ethyl acrylate/methylol             acrylamide             = 47.5/47.5/5 mole %             Emulsifier used: dodecyl sulfate-             polyoxymethylene (3 moles) and sodium ether             (3% based on monomer)    C        Aqueous dispersion of polyurethane resin             (aqueous dispersion obtained by neutralizing             an aqueous polyurethane dispersion produced by             reacting 94 parts of polyester having the             below-mentioned composition, 6 parts of 2, 2-             dimethylol propionic acid and 11 parts of             isophorone-di-isocyanate with each other, with             triethyl amine):             Composition of polyester:             Terephthalic acid/isophthalic acid/ethylene             glycol/diethylene glycol             = 60/40/61/39 mole %    D        Aqueous dispersion of oxazoline resin             (emulsion polymer obtained by polymerizing the             below-mentioned components at the below-             mentioned molar ratio):             Styrene/butyl acrylate/2-isopropenyl-2-             oxazoline/divinyl benzene             = 68.1/21.8/10/0.1 mole %             Emulsifier used: polyoxyethylene-alkylphenyl             ether-sodium sulfate (3% based on monomer)    E        Silane coupling agent (3-glycidoxypropyl-             trimethoxy silane)    F        Hexamethoxymethyl melamine    G        Aqueous dispersion of modified bisphenol A-             type epoxy resin ("DENAKOL EX-1103" produced             by NAGASE KASEI CO., LTD.)    H        Aqueous dispersion of blocked isocyanate             ("ELASTRON MF-9" produced by DAIIOHI KOGYO             SEIYAKU CO., LTD.)    I        Aqueous dispersion of acryl-grafted epoxy             resin (graft polymer obtained by polymerizing             monomers (50% as a total amount) having the             below-mentioned composition in water) in the             presence of a reaction product of 2, 2-bis(4-             hydroxyphenyl) propane and epichlorohydrin             (50%)             Methacrylic acid/ethyl acrylate/styrene             = 2/50/48%             Incidentally, dimethyl-ethanol amine was used             as a neutralizing agent for methacrylic acid             to assist the formation of aqueous dispersion.             Trimethoxymethyl melamine was further added to             the aqueous dispersion to produce the raw             coating material. The amount of             trimethoxymethyl melamine added was 5% based             on the solid content in the aqueous             dispersion.    J        Aqueous dispersion of silicon oxide (particle             diameter: 0.06 μm)    ______________________________________

                                      TABLE 5    __________________________________________________________________________           Comp.                Comp.                    Comp.                         Comp.    Properties           Ex. 1                Ex. 2                    Ex. 3                         Ex. 4                             Ex. 1                                 Ex. 2                                    Ex. 3                                        Ex. 4    __________________________________________________________________________    Optical density           0.05 1.49                    0.05 1.49                             1.48                                 1.52                                    0.50                                        1.52    Heat shrinkage    percentage    MD (%) 3.5  15.0                    2.8  12.0                             2.8 2.8                                    2.4 2.8    TD (%) 1.0  15.0                    0.8  12.0                             0.4 0.4                                    0.4 0.4    Suitability for    decorative    sheet    <Change in           X    ◯                    X    ◯                             ◯                                 ◯                                    ◯    color tone>    <Surface           ◯                X   ◯                         X   ◯                                 ◯                                    ◯                                        ◯    condition>    <Easiness in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ⊚                                        ◯    embossing>    <Adhesion>    Manual X    X   Δ                         Δ                             Δ                                 Δ                                    Δ                                        Δ    Creep  X    X   Δ                         Δ                             Δ                                 Δ                                    Δ                                        Δ    __________________________________________________________________________                                 Ex.                                    Ex. Ex.    Properties           Ex. 5                Ex. 6                    Ex. 7                         Ex. 8                             Ex. 9                                 10 11  12    __________________________________________________________________________    Optical density           1.52 1.52                    1.52 1.48                             1.52                                 0.50                                    1.48                                        1.52    Heat shrinkage    percentage    MD (%) 2.8  2.8 2.8  3.5 3.5 3.0                                    3.5 3.5    TD (%) 0.4  0.4 0.4  0.5 0.5 0.5                                    0.5 0.5    Suitability for    decorative    sheet    <Change in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    color tone>    <Surface           ◯◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯    condition>    <Easiness in           ◯                ◯                    ◯                         ◯                             ◯                                 ⊚                                    ◯                                        ◯    embossing>    <Adhesion>    Manual ◯                ◯                    Δ                         Δ                             Δ                                 Δ                                    Δ                                        Δ    Creep  ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    __________________________________________________________________________           Ex.  Ex. Ex.  Ex. Ex. Ex.                                    Ex. Ex.    Properties           13   14  1.5  16  17  18 19  20    __________________________________________________________________________    Optical density           0.50 1.48                    1.52 0.50                             1.48                                 1.52                                    0.50                                        1.48    Heat shrinkage    percentage    MD (%) 3.0  3.5 3.5  3.0 3.5 3.5                                    3.0 3.5    TD (%) 0.5  0.5 0.5  0.5 0.5 0.5                                    0.5 0.5    Suitability for    decorative    sheet    <change in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯    color tone>    <Surface           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    condition>    <Easiness in           ⊚                ◯                    ◯                         ⊚                             ◯                                 ◯                                    ⊚                                        ◯    embossing>    <Adhesion>    Manual Δ                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    Creep  ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    __________________________________________________________________________           Ex.  Ex. Ex.  Ex. Ex. Ex.                                    Ex. Ex.    Properties           21   22  23   24  25  26 27  28    __________________________________________________________________________    Optical density           1.52 0.50                    1.52 1.52                             1.52                                 1.52                                    1.52                                        1.52    Heat shrinkage    percentage    ND (%) 3.5  3.0 3.5  3.5 3.5 3.5                                    3.5 3.5    TD (%) 0.5  0.5 0.5  0.5 0.5 0.5                                    0.5 0.5    Suitability for    decorative    sheet    <Change in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    color tone>    <Surface           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    condition>    <Easiness in           ◯                ⊚                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    embossing>    <Adhesion>    Manual ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    Creep  ◯                ◯                    ⊚                         ⊚                             ◯                                 ⊚                                    ⊚                                        ◯    __________________________________________________________________________           Ex.  Ex. Ex.  Ex. Ex. Ex.                                    Ex. Ex.    Properties           29   30  31   32  33  34 35  36    __________________________________________________________________________    Optical density           1.52 1.52                    1.52 1.52                             1.52                                 1.52                                    1.52                                        1.52    Heat shrinkage    percentage    MD (%) 3.5  3.5 3.5  3.5 3.5 3.5                                    3.5 3.5    TD (%) 0.5  0.5 0.5  0.5 0.5 0.5                                    0.5 0.5    Suitability for    decorative    sheet    <Change in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    color tone>    <Surface>           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    condition>    <Easiness in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    embossing>    <Adhesion>    Manual ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    Creep  ⊚                ◯                    ◯                         ⊚                             ⊚                                 ◯                                    ◯                                        ⊚    __________________________________________________________________________           Ex.  Ex. Ex.  Ex. Ex. Ex.                                    Ex. Ex.    Properties           37   38  39   40  41  42 43  44    __________________________________________________________________________    Optical density           1.52 1.52                    1.52 1.52                             1.52                                 1.52                                    1.52                                        1.52    Heat shrinkage    percentage    MD (%) 3.5  3.5 3.5  3.5 3.5 3.5                                    3.5 3.5    TD (%) 0.5  0.5 0.5  0.5 0.5 0.5                                    0.5 0.5    Suitability for    decorative    sheet    <Change in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    color tone>    <Surface>           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    condition>    <Easiness in           ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    embossing>    <Adhesion>    Manual ◯                ◯                    ◯                         ◯                             ◯                                 ◯                                    ◯                                        ◯    Creep  ◯                ⊚                    ⊚                         ◯                             ⊚                                 ◯                                    ⊚                                        ⊚    __________________________________________________________________________    Properties           Ex. 45                Ex. 46    __________________________________________________________________________    Optical density           1.52 1.52    Heat shrinkage    percentage    MD (%) 3.5  3.5    TD (%) 0.5  0.5    Suitability for    decorative    sheet    <Change in           ◯                ◯    color tone>    <Surface>           ◯                ◯    condition>    <Easiness in           ◯                ◯    embossing>    <Adhesion>    Manual ◯                ◯    Creep  ◯                ⊚    __________________________________________________________________________

Comparative Example 5 and Examples 48 to 139

The measuring methods used in the below-mentioned Examples andComparative Examples were as follows.

(8) Optical Density: Measured According to the Same Method as Describedin "(1) Hiding Power" Hereinbefore

(10) Tensile Modulus

A sample film having a length of 300 mm and a width of 20 mm was placedin an atmosphere maintained at a temperature of 23° C. and a relativehumidity of 50%, and stretched at a straining rate of 10% per minute byusing a tension tester ("INTESCO-MODEL 2001", manufactured by INTESCOCO., LTD.) to obtain a tensile stress-strain characteristic curve. Usingan initial linear part of the thus-obtained tensile stress-straincharacteristic curve, the tensile modulus of the polyester film wascalculated from the following formula:

    E=Δσ/Δε

wherein E represents a tensile modulus (kg/mm²), Δσ represents adifference in stress between two points on the linear part based on anoriginal average cross-sectional area, and Δε represents a difference instrain between the two points.

(11) Suitability for V-cut Processing

A decorative sheet having the below-mentioned configuration waslaminated over a plywood as a flat base material whose surface had ablack color tone, to produce a decorative plate. The thus-produceddecorative plate was subjected to V-cut processing to form a V-cutgroove thereon and bent therealong. Thereafter, the bent decorativeplate was observed as to whether or not the plate returned to itsoriginal flat shape, to determine the suitability for V-cut processingthereof. The results of the observation were classified into thefollowing ranks:

∘: Not returned to the original flat shape, i.e., maintained the bentshape; and

X: Returned to the original flat shape

Among those involved in the first rank "∘", extremely excellent oneswere indicated by the symbol "⊚".

In accordance with the present invention, those indicated by the symbols"∘" and "⊚" are suitable.

The decorative sheet was prepared in the following manner. First, anoptional picture pattern was printed on an inner film. A 50 μnm-thickpolyester film ("T600-50" produced by DIAFOIL HOECHIST CO., LTD.) or a50 μm-thick acryl film ("ACRYPRENE HBS" produced by MITSUBISHI RAYONCO., LTD.) as an outer film was laminated over the printed inner film toproduce the decorative sheet. The above lamination was conducted byusing a saturated polyester resin-based adhesive ("NICHIGO-POLYESTERLP-035" produced by NIPPON GOSEI KAGAKU CO., LTD.). Next, thethus-produced decorative sheet was laminated over the plywood as a flatbase material to produce a decorative plate laminated by clear film. Thelamination of the decorative sheet over the plywood was performed insuch a manner that the inner film of the decorative sheet faced andadhered to the plywood. Five kinds of adhesives shown in Table 1 wereused for the lamination. The resultant decorative plate was tested withrespect to suitability for V-cut processing while varying the kinds ofadhesives used. The suitability for V-cut processing of the decorativeplate was finally determined as an average of measured values obtainedrespectively by using the five adhesives.

(12) Resistance to Impact Deformation

The afore-mentioned decorative plate was placed at a horizontal planesuch that the decorative sheet faced upward. An iron ball having aweight of 100 g and a diameter of 3 cm was dropped from 50 cm heightonto the decorative plate. The picture pattern on the decorative platewas observed at a position at which the iron ball was dropped, todetermine whether or not any dent by falling ball was caused. Theresults of the observation were classified into the following ranks.

∘: No dent by falling ball was recognized.

X: Dent by falling ball was clearly recognized.

Δ: Dent by falling ball was in an intermediate condition between theabove two ranks.

(13) Hiding Property

The picture pattern printed on the decorative sheet was observed from afront surface side thereof to determine whether or not any change incolor tone thereof occurred. The results of the observation wereclassified into the following ranks:

∘: No change in color tone occurred and its design value was maintained;

X: Considerable change in color tone and deterioration in design valueoccurred; and

Δ: Intermediate condition between the above two ranks.

Among those involved in the first rank "∘", extremely excellent oneswere indicated by the symbol "⊚".

In accordance with the present invention, those indicated by the symbols"Δ", "∘" and "⊚" are suitable.

(14) Adhesion Property

A decorative sheet was prepared in the following manner. First, anoptional picture pattern was printed on an inner film. A 50 μm-thickpolyester film ("T600-50" produced by DIAFOIL HOECHIST CO., LTD.) or a50 μm-thick acryl film ("ACRYPRENE HBS" produced by MITSUBISHI RAYONCO., LTD.) as an outer film was laminated over the printed inner film toproduce the decorative sheet. Upon laminating, a saturated polyesterresin-based adhesive ("NICHIGO-POLYESTER LP-035" produced by NIPPONGOSEI KAGAKU CO., LTD.) was used. Next, the thus-produced decorativesheet was laminated over the plywood as a flat base material to producea decorative plate laminated by clear film. The lamination of thedecorative sheet over the plywood was performed in such a manner asdescribed in "(7) Adhesion property" hereinbefore. Five kinds ofadhesives shown in Table 1 were used for the lamination. The resultantdecorative plate was tested with respect to adhesion property thereofwhile varying the kinds of adhesives used. The adhesion property of thedecorative plate was finally determined as an average of measured valuesobtained respectively by using the five adhesives.

The layer (ply) separation of the decorative plate is most likely tooccur at a boundary surface between the plywood and the inner film.Accordingly, the adhesion property of the decorative plate was evaluatedat this portion by the methods described in "(7-1) Manual peeling test"and "(7-2) High-temperature creep peeling test" of "(7) AdhesionProperty" hereinbefore.

Production Example 4

Polyethylene terephthalate containing 13.5% by weight of titaniumdioxide and 0.5% by weight of wet silica was dried at 180° C. for 4hours. The polyethylene terephthalate was extruded at 290° C. by using amelt-extruder. Using an electrostatic pinning method, the extrudedpolyethylene terephthalate was cooled and solidified by passing over acooling roll whose surface was maintained at 40° C., to obtain anunstretched film. The thus-obtained unstretched film was stretched 2.5times in the longitudinal direction at 85° C., thereby obtaining alongitudinally stretched film.

Next, the thus-obtained longitudinally stretched film was introducedinto a tentering machine, stretched 3.2 times in the lateral directionby a tentering machine at 120° C. and thereafter heat-set at 210° C.,thereby obtaining a biaxially stretched polyester film (VI) having athickness of 50 μm.

Production Example 5

The same procedure as in Example 4 was conducted except that the amountsof titanium dioxide and wet silica to be added to the polyethyleneterephthalate were changed to 7.0% by weight and 0.5% by weight,respectively, to obtain a biaxially stretched polyester film (VII).

Production Example 6

The same procedure as in Example 4 was conducted except that 7.3% byweight of titanium dioxide, 0.01% by weight of carbon black, 0.2% byweight of red oxide, 0.4% by weight of anthraquinone-based yellowpigment and 0.5% by weight of wet silica were added to polyethyleneterephthalate, to obtain a biaxially stretched polyester film (VIII).

Production Example 7

Polyethylene terephthalate having 30 mol % of an isophthalic acidcomponent and containing 7.3% by weight of titanium dioxide, 0.01% byweight of carbon black, 0.2% by weight of iron oxide red, 0.4% by weightof anthraquinone-based yellow pigment and 0.5% by weight of wet silica,was dried at 70° C. for one week in a vacuum dryer. Thereafter, thedried polyethylene terephthalate was extruded at 250° C. by using amelt-extruder. Using an electrostatic pinning method, the extrudedpolyethylene terephthalate was cooled and solidified by passing over acooling roll whose surface was maintained at 10° C., thereby obtainingan unstretched polyethylene terephthalate film was obtained. Thethus-obtained unstretched polyethylene terephthalate film was stretched2.5 times in the longitudinal direction at 50° C., thereby obtaining alongitudinally stretched film.

Next, the thus-obtained longitudinally stretched film was stretched 3.0times in the lateral direction by a tentering machine at 90° C. andthereafter, heat-set at 150° C., thereby obtaining a biaxially stretchedpolyester film (IX) having a thickness of 50 μm.

Production Example 8

The same procedure as in Example 4 was conducted except thatpolyethylene terephthalate to which 0.6% by weight of titanium dioxideand 0.5% by weight of wet silica were added, was extruded and then theextruded polyethylene terephthalate was cooled and solidified by passingover a cooling roll but not subjected to stretching, thereby obtainingan unstretched polyester film (X) having a thickness of 100 μm.

Production Example 9

The same procedure as in Example 4 was conducted except thatpolyethylene terephthalate to which 5% by weight of titanium dioxide and0.5% by weight of wet silica were added, was used, thereby obtaining abiaxially stretched polyester film (XI) having a longitudinal tensilemodulus of 500 kg/mm² and a transverse tensile modulus of 550 kg/mm².

Comparative Example 5

Using polyethylene terephthalate, the same procedure as in ProductionExample 4 was conducted to produce a biaxially-stretched polyester film(XII) whose longitudinal and transverse tensile moduli were adjusted to610 kg/mm² and 570 kg/mm², respectively. By using the thus-producedbiaxially-stretched polyester film as an inner film and theafore-mentioned polyester film ("T600-50" produced by DIAFOIL HOECHISTCO., LTD.) as an outer film, a decorative plate laminated by clear filmwas produced in the same manner as described above, and the propertiesthereof were evaluated. The results are shown in Table 7.

Example 48

A biaxially-stretched polyester film provided with a coating layer wasproduced. The combination of the coating layer and the base film used isshown in Table 6. Specifically, the coating layer 1 was formed on onesurface of the polyester film (VI) produced in Comparative Example 8.The composition of the coating layer 1 is shown in Table 3. The detailedcomposition of the raw coating materials used are shown in Table 4. Byusing the thus-produced biaxially-stretched polyester film as an innerfilm and the afore-mentioned polyester film ("T600-50" produced byDIAFOIL HOECHIST CO., LTD.) as an outer film, a decorative platelaminated by clear film was produced in the same manner as describedabove, and the properties thereof were evaluated. The properties of theobtained coated polyester film are shown in Table 7. As seen from Table7, the obtained coated polyester film was satisfactory in suitabilityfor decorative plates including the adhesion property thereof.Incidentally, the adhesion property of the polyester film was evaluatedwith respect to the surface thereof on which the coating layer isformed.

Examples 49 to 61 and Comparative Example 6

The same procedure as in Example 48 was conducted except that thecombination of the coating layer and the base film used was changed asshown in Table 6 and the composition and film thickness of the coatinglayer were changed as shown in Tables 3 and 4, to produce coated films.The properties of the thus-produced coated films are shown in Table 1.The coated films produced in Examples 49 to 61 all were excellent insuitability for decorative plate including the adhesion propertythereof, while the coated film produced in Comparative Example 6 wassatisfactory only in adhesion property but unsatisfactory in suitabilityfor V-cut processing.

Example 62

A coated film was produced in the same manner as in Example 48 exceptthat a coating layer was formed on a base film in the course ofsubjecting the base film to the longitudinal and transverse stretching.Specifically, after the polyester base film was stretched in thelongitudinal direction but before it was stretched in the transversedirection, the coating solution was applied onto one surface of the basefilm to form the coated polyester film. Thereafter, the coated polyesterfilm was stretched in the transverse direction and heat-set to produce acoated biaxially-stretched polyester film. The coating solution wasprepared in the same manner as in Example 48, and applied onto thepolyester base film by a roll coater. Notwithstanding the thickness ofthe dried coating layer was as low as one third of that of Example 48due to the transverse stretching, the coating layer showed a goodadhesive property. It was considered that these effects were obtained byusing the in-line coating method. The properties of the obtained coatedpolyester film are shown in Table 7. As seen from Table 7, the coatedpolyester film are satisfactory in suitability for decorative plate.

Examples 63 to 139

Coated films were produced in the same manner as in Example 62, i.e., byin-line coating method, except that the combination of the coating layerand the base film used was changed as shown in Table 6. In any case,after the polyester base film was stretched in the longitudinaldirection but before it was stretched in the transverse direction, thecoating solution was applied onto one surface of the base film to formthe coated polyester film. Thereafter, the coated polyester film wasstretched in the transverse direction and heat-set to produce a coatedbiaxially-stretched polyester film. The application of the coatingsolution onto the base film was conducted in the same manner as inExample 62. The compositions and film thicknesses of the obtainedcoating layers are shown in Table 3. Production conditions other thanthe application of the coating solution were the same as those used forthe production of the respective base films. The properties of theobtained coated films are shown in Table 7. Although all the coatinglayers had thicknesses as small as one third of those of Examples 48 to61, the coated films were satisfactory in suitability for decorativeplate including the adhesion property thereof. Especially in the casewhere the coating layers contained a cross-linking agent, the resultantcoated polyester films were above to frequently exhibit a high adhesionproperty even at an elevated temperature.

                                      TABLE 6    __________________________________________________________________________    Coating        Base film    layer        VI   VII  VIII IX   X    XI   XII    __________________________________________________________________________    None        --   --   --   --   --   --   Comp.                                      Ex. 5    Coating        Ex. 48             Ex. 49                  Ex. 50                       Ex. 51                            Ex. 52                                 Ex. 53                                      Comp.    layer 1                           Ex. 6    Coating        --   --   Ex. 54                       Ex. 55                            --   --   --    layer 2    Coating        --   --   Ex. 56                       Ex. 57                            --   --   --    layer 3    Coating        --   --   Ex. 58                       Ex. 59                            --   --   --    layer 4    Coating        --   --   Ex. 60                       Ex. 61                            --   --   --    layer 5    Coating        Ex. 62             Ex. 63                  Ex. 64                       Ex. 65                            Ex. 66                                 Ex. 67                                      --    layer 6    Coating        Ex. 68             Ex. 69                  Ex. 70                       Ex. 71                            Ex. 72                                 Ex. 73                                      --    layer 7    Coating        Ex. 74             Ex. 75                  Ex. 76                       Ex. 77                            Ex. 78                                 Ex. 79                                      --    layer 8    Coating        Ex. 80             Ex. 81                  Ex. 82                       Ex. 83                            Ex. 84                                 Ex. 85                                      --    layer 9    Coating        Ex. 86             Ex. 87                  Ex. 88                       Ex. 89                            Ex. 90                                 Ex. 91                                      --    layer 10    Coating        --   --   Ex. 92                       Ex. 93                            --   --   --    layer 11    Coating        --   --   Ex. 94                       Ex. 95                            --   --   --    layer 12    Coating        --   --   Ex. 96                       Ex. 97                            --   --   --    layer 13    Coating        --   --   Ex. 98                       Ex. 99                            --   --   --    layer 14    Coating        --   --   Ex. 100                       Ex. 101                            --   --   --    layer 15    Coating        --   --   Ex. 102                       Ex. 103                            --   --   --    layer 16    Coating        --   --   Ex. 104                       Ex. 105                            --   --   --    layer 17    Coating        --   --   Ex. 106                       Ex. 107                            --   --   --    layer 18    Coating        --   --   Ex. 108                       Ex. 109                            --   --   --    layer 19    Coating        --   --   Ex. 110                       Ex. 111                            --   --   --    layer 20    Coating        --   --   Ex. 112                       Ex. 113                            --   --   --    layer 21    Coating        --   --   Ex. 114                       Ex. 115                            --   --   --    layer 22    Coating        --   --   Ex. 116                       Ex. 117                            --   --   --    layer 23    Coating        --   --   Ex. 118                       Ex. 119                            --   --   --    layer 24    Coating        --   --   Ex. 120                       Ex. 121                            --   --   --    layer 25    Coating        --   --   Ex. 122                       Ex. 123                            --   --   --    layer 26    Coating        --   --   Ex. 124                       Ex. 125                            --   --   --    layer 27    Coating        --   --   Ex. 126                       Ex. 127                            --   --   --    layer 28    Coating        --   --   Ex. 128                       Ex. 129                            --   --   --    layer 29    Coating        --   --   Ex. 130                       Ex. 131                            --   --   --    layer 30    Coating        --   --   Ex. 132                       Ex. 133                            --   --   --    layer 31    Coating        --   --   Ex. 134                       Ex. 135                            --   --   --    layer 32    Coating        --   --   Ex. 136                       Ex. 137                            --   --   --    layer 33    Coating        --   --   Ex. 138                       Ex. 139                            --   --   --    layer 34    __________________________________________________________________________

                                      TABLE 7    __________________________________________________________________________            Comp.                Comp.                     Ex. Ex. Ex. Ex. Ex. Ex.    Properties            Ex. 5                Ex. 6                     48  49  50  51  52  53    __________________________________________________________________________    Optical density            0.1 0.1  0.8 0.5 1.7 1.7 0.1 0.4    Tensile modulus    MD (kg/mm.sup.2)            610 610  440 440 440 300 190 500    TD (kg/mm.sup.2)            560 560  480 480 480 300 190 550    Suitability for    decorative    sheet    <Suitability            X   X    ◯                         ◯                             ◯                                 ⊚                                     ⊚                                         ◯    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            Δ                Δ                     ⊚                         ⊚                             ⊚                                 ⊚                                     Δ                                         ◯    Power>    <Adhesion>    Manual  X   Δ                     Δ                         Δ                             Δ                                 Δ                                     Δ                                         Δ    Creep   X   Δ                     Δ                         Δ                             Δ                                 Δ                                     Δ                                         Δ    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            54  55   56  57  58  59  60  61    __________________________________________________________________________    Optical density            1.7 1.7  1.7 1.7 1.7 1.7 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  Δ                Δ                     ◯                         ◯                             ◯                                 ◯                                     Δ                                         Δ    Creep   Δ                Δ                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            62  63   64  65  66  67  68  69    __________________________________________________________________________    Optical density            0.8 0.5  1.7 1.7 0.1 0.4 0.8 0.5    Tensile modulus    MD (kg/mm.sup.2)            440 440  440 300 190 500 440 440    TD (kg/mm.sup.2)            480 480  480 300 190 550 480 480    Suitability for    decorative    sheet    <Suitability            ◯                ◯                     ◯                         ⊚                             ⊚                                 ◯                                     ◯                                         ◯    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             Δ                                 ◯                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  Δ                Δ                     Δ                         Δ                             Δ                                 Δ                                     Δ                                         Δ    Creep   ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            70  71   72  73  74  75  76  77    __________________________________________________________________________    Optical density            1.7 1.7  0.1 0.4 0.8 0.5 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 300  190 500 440 440 440 300    TD (kg/mm.sup.2)            480 300  190 550 480 480 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ⊚                         ◯                             ◯                                 ◯                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     Δ                         ◯                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  Δ                Δ                     Δ                         Δ                             ◯                                 ◯                                     ◯                                         ◯    Creep   ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            78  79   80  81  82  83  84  85    __________________________________________________________________________    Optical density            0.1 0.4  0.8 0.5 1.7 1.7 0.1 0.4    Tensile modulus    MD (kg/mm.sup.2)            190 500  440 440 440 300 190 500    TD (kg/mm.sup.2)            190 550  480 480 480 300 190 550    Suitability for    decorative    sheet    <Suitability            ⊚                ◯                     ◯                         ◯                             ◯                                 ⊚                                     ⊚                                         ◯    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            Δ                ◯                     ⊚                         ⊚                             ⊚                                 ⊚                                     Δ                                         ◯    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            86  87   88  89  90  91  92  93    __________________________________________________________________________    Optical density            0.8 0.5  1.7 1.7 0.1 0.4 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 440  440 300 190 500 440 300    TD (kg/mm.sup.2)            480 480  480 300 190 550 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ◯                     ◯                         ⊚                             ⊚                                 ◯                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             Δ                                 ◯                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            94  95   96  97  98  99  100 101    __________________________________________________________________________    Optical density            1.7 1.7  1.7 1.7 1.7 1.7 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ⊚                ⊚                     ◯                         ◯                             ⊚                                 ⊚                                     ⊚                                         ⊚    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            102 103  104 105 106 107 108 109    __________________________________________________________________________    Optical density            0.1 0.1  0.8 0.5 1.7 1.7 0.1 0.4    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ◯                ◯                     ⊚                         ⊚                             ◯                                 ◯                                     ◯                                         ◯    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            110 111  112 113 114 115 116 117    __________________________________________________________________________    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            118 119  120 121 122 123 124 125    __________________________________________________________________________    Optical density            1.7 1.7  1.7 1.7 1.7 1.7 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ⊚                ⊚                     ◯                         ◯                             ⊚                                 ⊚                                     ⊚                                         ⊚    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            70  71   72  73  74  75  76  77    __________________________________________________________________________    Optical density            1.7 1.7  1.7 1.7 1.7 1.7 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚                                     ◯                                         ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚                                     ⊚                                         ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯                                     ◯                                         ◯    Creep   ◯                ◯                     ⊚                         ⊚                             ◯                                 ◯                                     ⊚                                         ⊚    __________________________________________________________________________            Ex. Ex.  Ex. Ex. Ex. Ex. Ex. Ex.    Properties            134 135  136 137 138 139    __________________________________________________________________________    Optical density            1.7 1.7  1.7 1.7 1.7 1.7    Tensile modulus    MD (kg/mm.sup.2)            440 300  440 300 440 300    TD (kg/mm.sup.2)            480 300  480 300 480 300    Suitability for    decorative    sheet    <Suitability            ◯                ⊚                     ◯                         ⊚                             ◯                                 ⊚    for V-cut    processing>    <resistance            ◯                ◯                     ◯                         ◯                             ◯                                 ◯    to impact    deformation>    <Hinding            ⊚                ⊚                     ⊚                         ⊚                             ⊚                                 ⊚    Power>    <Adhesion>    Manual  ◯                ◯                     ◯                         ◯                             ◯                                 ◯    Creep   ⊚                ⊚                     ◯                         ◯                             ⊚                                 ⊚    __________________________________________________________________________

What is claimed is:
 1. A polyester film for decorative plate ordecorative sheet, which comprises a base polyester film and a coatinglayer formed on at least one surface of said base polyester film,wherein said polyester film for decorative plate or decorative sheet hasan optical density of 0.1 to 5.0 and longitudinal and transverse heatshrinkage percentages of not less than -10.0% and not more than +10.0%after said polyester film for decorative plate or decorative sheet isheat-treated at 180° C. for 5 minutes.
 2. A polyester film according toclaim 1, wherein said coating layer comprises at least one compoundselected from the group consisting of a polyester resin, an acrylicresin, a polyurethane resin, an amino resin, an epoxy resin, anoxazoline resin and a coupling agent.
 3. A polyester film according toclaim 1, wherein said coating layer is formed by in-line coating method.4. A decorative plate comprising a substrate and at least a polyesterfilm layer comprising the polyester film according to claim 1 and aprinted layer, wherein said printed layer is laminated on said basepolyester film and wherein said coating layer is laminated on saidsubstrate.
 5. A decorative sheet comprising a polyester film layercomprising the polyester film according to claim 1 and a printed layerformed on said base polyester film of said film layer.
 6. A polyesterfilm for decorative laminated plate, which comprises a base polyesterfilm and a coating layer formed on at least one surface of said basefilm, wherein said polyester film for decorative laminated plate haslongitudinal and transverse tensile moduli of not more than 600 kg/mm².7. A polyester film according to claim 6, wherein said polyester filmhas longitudinal and transverse tensile moduli of not less than 190kg/mm².
 8. A polyester film according to claim 6, wherein said coatinglayer comprises at least one compound selected from the group consistingof a polyester resin, an acrylic resin, a polyurethane resin, an aminoresin, an epoxy resin, an oxazoline resin and a coupling agent.
 9. Apolyester film according to claim 6, wherein said coating layer isformed by in-line coating method.
 10. A decorative laminated plate,which comprises a substrate, at least a first adhesive layer, an innerfilm layer comprising the polyester film for decorative laminated plateaccording to claim 6, a printed layer, a second adhesive layer and anouter film layer, wherein said outer film layer is laminated over saidsecond adhesive layer, said second adhesive layer is laminated over saidprinted layer, said printed layer is laminated over said polyester filmfor decorative laminated plate, said polyester film for decorativelaminated plate is laminated over said first adhesive layer, and saidfirst adhesive layer is laminated over said substrate.